Addressing the Epidemic of Obesity in the United States Fire Service

Transcription

Addressing the Epidemic of Obesity
in the United States Fire Service
A Report Prepared for the National Volunteer Fire Council
Obesity
Supporting Those Who Serve
Addressing the Epidemic of Obesity
in the United States Fire Service
A Report Prepared for the National Volunteer Fire Council by:
Christopher K. Haddock, Ph.D.
Walker S.C. Poston, Ph.D., MPH
Sara A. Jahnke, Ph.D.
Center for Fire, Rescue, and EMS Health Research
National Development and Research Institutes, LLC
Obesity
Supporting Those Who Serve
National Volunteer Fire Council
7852 Walker Drive, Suite 450
Greenbelt, MD 20770
www.nvfc.org
©2011
12
6
20
20
4 Introduction
5 Executive Summary
6 Chapter 1
Obesity and Its Impact
12 Chapter 2
48
Obesity in the Fire Service
20 Chapter 3
Why Is There An Epidemic of Obesity in the Fire Service?
35 Chapter 4
Innovative Trends in Obesity and Fitness
Research
48 Chapter 5
Recommendations for the Fire Service for
Combating Obesity and Increasing Fitness
This report was developed by a cooperative agreement between the National Volunteer Fire Council
and the United States Fire Administration.
Introduction
When we think about the typical individual who excels in a
job, stereotypes automatically come to mind based on the
requirements of that occupation. Imagining a trusted physician evokes the image of someone who is intelligent, compassionate, and caring. Stereotypes of United State Marines
include bravery, commitment, and a high level of fitness.
What comes to your mind when you think of a firefighter?
Traditionally, firefighters were fodder for impressive photos in calendars and were known as icons of fitness and
strength. Classic images of firefighters include a reassuring
combination of technical skill, physical fitness, and bravery.
From a young age, we think of our firefighters as being able
to carry us from a burning building, run up flights of stairs,
and break down doors to rescue a loved one. Our nation
depends on the fire service to respond to nearly every major
domestic emergency that occurs at a moment’s notice. Few
would disagree that firefighters should maintain a high level
of physical fitness, including aerobic and anaerobic fitness,
flexibility, and muscular endurance, strength, and power.
Without high levels of health and fitness, firefighters may not
be able to perform the strenuous physical requirements of
their job and they risk injury and even death for themselves,
their comrades, and those they serve.
Are the classic images of firefighters as healthy, fit, and
strong still accurate? Although firefighters’ bravery and commitment to public service has never been in doubt, a chilling epidemic has been slowly developing in the fire service
which threatens their ability to effectively respond to the
emergencies and disasters that will inevitably occur in our
country. As in our nation at large, the number of individuals
who are overweight, obese, and unfit has risen to alarming
levels in fire departments, both volunteer and career, across
our nation. In fact, the best evidence suggests that rates of
the overweight and obese are higher in the fire service than
in the general public.
This report will urge everyone from national fire service
leadership, to department chiefs, to individual firefighters
to think creatively and join in efforts to reverse the negative
trends of unhealthy body weight and poor physical fitness.
It is time to begin a national conversation regarding obesity
in the fire service. This report provides basic data which can
be used to educate yourself and your colleagues about the
epidemic and provides suggestions you can use to address
fitness in your department.
4
The content of this report is for informational purposes only. It is not a substitute
for advice from your physician. You should seek prompt medical care for any
specific health issues; only your healthcare provider should diagnose a medical
condition and prescribe treatment. You may also wish to consult with your health
care professional or nutritionist before starting a new diet or fitness regimen.
About the Authors
Although the National Volunteer Fire Council (NVFC) and a
large number of firefighters have provided valuable feedback on the information in this publication, the opinions
expressed and any errors belong to the authors and do not
necessarily represent the official position of the NVFC. The
authors are well-versed in the subject matter and have conducted nutrition and fitness research for over two decades,
including the largest studies of obesity, physical activity,
and nutrition in the fire service conducted to date. They
have been involved in a large number of safety and health
initiatives in the fire service and have worked in over 100
firehouses nationwide. As certified fitness instructors, they
have personally conducted body composition and fitness
assessments on well over 1,000 firefighters from Hawaii to
the East Coast and spend much of the year working directly
with firefighters.
The authors care deeply about the fire service and are
honored to write this document. If you have any questions or
would like to provide useful information or ideas regarding
addressing obesity and fitness in the fire service, please feel
free to email the authors at the addresses below:
Christopher K. Haddock, Ph.D.
[email protected]
Walker S.C. Poston, Ph.D., MPH
[email protected]
Sara A. Jahnke, Ph.D.
[email protected]
Executive Summary
Chapter 1
Chapter 3
> More than two-thirds of Americans are overweight or obese.
Why Is There An Epidemic of Obesity in the
Fire Service?
> The rates of obesity have increased dramatically since the 1980s when only 13 percent of adults were considered obese.
> The nutrition environment in many firehouses appears to rein-
force poor eating habits and unhealthy nutrition.
> Overweight and obese individuals are at increased risk for metabolic syndrome, cardiovascular disease, hypertension, diabetes, cancer, and sleep disorders.
> Attempts to improve nutrition in the firehouse often are met with resistance.
> The direct and indirect costs of obesity are staggering and include greater absenteeism at work, lower worker productivity, and greater disability than those who maintain a healthy weight.
Chapter 2
> Rates of overweight and obese individuals in the fire service are higher than those found in the general public, ranging from 73 percent to 88 percent of firefighters.
> The high rates of obesity in the fire service do not appear to be due to inaccuracy in measurement.
> Research demonstrates that a large percentage of firefighters do not meet minimal standards of physical fitness.
> Occupational factors may place firefighters at high risk for weight gain, including shift work, sleep disruption, unhealthy eating patterns in the firehouse, and the absence of fitness standards for firefighters.
> Overweight and obese firefighters have been shown to suffer from a large number of problems compared to their colleagues, including hypertension, higher risks for cardiovascular disease, low fitness, reduced muscular strength, and more frequent cardiac events.
> Overweight and obese firefighters are less fit to perform their jobs and cost fire departments significantly more than
firefighters with a healthy weight.
> Several initiatives have attempted to address the high levels of overweight, obese, and unfit firefighters, including NFPA 1583: Standard on Health-Related Fitness Programs for Fire Department Members, NFPA 1582: Standard on Comprehen-
sive Occupational Medical Programs for Fire Departments, the NVFC’s Heart-Healthy Firefighter Program, the NVFC and U.S.
Fire Administration’s Health and Wellness Guide for the Volunteer Fire and Emergency Services, and the International Association of Fire Fighters/International Association of Fire Chiefs Wellness/Fitness Initiative.
> Firefighters often consume diets high in processed carbo-
hydrates and sugar, which promote obesity and cardiovascular disease.
> Diets that keep insulin levels stable and focus on foods with a low glycemic index promote a healthy body composition and improved performance.
> Firefighters overestimate the ability of physical activity to counteract the impact of large food portions or unhealthy dietary choices.
Chapter 4
Innovative Trends in Obesity and Fitness
Research
> Firefighters should eat natural, whole foods and avoid
processed foods, fast foods, and sugar.
> The Slow Food Movement encourages a return to traditional cooking methods and a focus on high-quality eating.
> Ancestral Eating teaches the benefits of returning to the diets on which humans evolved and warns of the problems of foods which have only recently entered our food supply.
> High Intensity Training is an effective, time-efficient form of exercise which is ideally suited for firefighters.
> Functional Exercise focuses on natural movements that mimic activities involved in firefighting.
> CrossFit® represents an exciting approach to fitness for
firefighters which stresses both high-intensity training and functional movements.
Chapter 5
Recommendations for the Fire Service for
Combating Obesity and Increasing Fitness
> Recommendations are provided for how firefighters can signifi-
cantly improve their nutrition.
> Fire departments should consider conducting annual fitness assessments.
> Minimal fitness recommendations for all firefighters should be a priority.
> An effective fitness program can be implemented by fire
departments at minimal cost and using existing facilities.
5
Chapter 1
Metabolic Syndrome I Cardiovascular Disease I Hypertension I Diabetes I Sleep Apnea I Cholestero
Chapter 1 Obesity and Its Impact
Obesity and Overweight in the United States
Obesity has become one of the leading health concerns among the medical and public health communities in the United States and is now considered to be
of epidemic proportions. Rates of obesity in the U.S.
are tracked through the National Health and Nutrition Examination Survey (NHANES).1 Data from
the most recent NHANES found that 33.8 percent of
Americans are obese and an additional 34.2 percent
are overweight. It has been estimated that every year
an estimated 112,000 preventable deaths occur due
to obesity.2 The dramatic increases in obesity and its
related medical disorders is a relatively recent occurrence compared to past decades. Before the 1980s, only
about 13 percent of adults were considered obese. While
rates in the past decade have been relatively stable, they
remain extremely high.
Definitions of Overweight & Obesity
Several definitions of overweight and obesity exist depending on the type of measure used. Body Mass Index
(BMI) is one of the most consistently used measures by
doctors, research, and the public health service.3 BMI
is calculated by using height and weight and, for most
people, is highly correlated with measured body fat.
Standard cutoffs for BMI have been set by the World
Health Organization as underweight (<18.5), healthy
weight (18.5 – 24.9), overweight (25.0 – 29.9), obesity
class I (30.0 – 34.9), obesity class II (35.0 – 39.9), and
obesity class III (>40.0).4
Calculating Your Body Mass Index (BMI)
BMI =
weight (kg)
height (m2)
OR
BMI = 703 x
weight (lbs)
height (in2)
Waist circumference (WC) is also commonly used to estimate overweight and obesity. Fat accumulation around
the waist is particularly detrimental to overall health
and is highly related to disease and death. The WC cutoff is >35 inches for women and >40 inches for men.
Clinical guidelines suggest that waist circumference may
be particularly helpful in determining increased risk for
dyslipidemia, hypertension, CVD, and type 2 diabetes
among people who are categorized as overweight using
BMI. This is because elevated waist circumference is an
independent marker of disease risk even among individuals thought to be at low or modest risk for disease
or death using BMI.
7
Body fat is another measure to determine overweight
and obesity and is considered the most accurate way
of estimating risk for disease and death. Several tools
are available for measuring body fat including calipers,
bioelectrical impedance, and dual energy X-ray absorptiometry (DXA). With calipers, measurements are taken
on three to eight prescribed spots on the body and
entered into an equation to estimate average body fat.
Bioelectrical impedance uses a minute electrical signal
that travels through the body and estimates body fat
based on age, gender, height, weight, and the speed of
the signal. DXA is a full body X-ray that is able to most
accurately measure the proportions of your body that
are fat, muscle mass, water, and bone. It is now considered to be the “gold standard” method against which all
other tools are measured.
The cut-offs defining obesity are based on the relationship between body composition and disease or death.
For example, those in the overweight or obese categories are at higher risk for diseases like stroke, type 2
diabetes, hypertension, coronary artery disease, osteoarthritis, sleep apnea or respiratory problems, dyslipidemia, and some cancers. (See Table 1 on page 8).
Why Obesity is a Problem
Although many people would like to be at a healthy
weight primarily for cultural or appearance reasons,
the medical community is concerned about obesity
because it raises the risk of suffering from a number of
significant health problems. The following is a review of
several medical problems associated with an unhealthy
body composition.
Metabolic syndrome is related to increased risk of cardiovascular disease, stroke, and diabetes. It is diagnosed
when a person has three or more of a designated list of
risk factors: (a) a waist circumference over 40 inches for
men and 35 inches for women; (b) serum triglycerides
of 150 mg/dL or higher; (c) high density lipoproteins
(HDL) levels below 40 mg/dL in men or 50 mg/dL in
women; (d) blood pressure over 130/85 mm Hg; and (e)
fasting glucose of more than 100 mg/dL. 5
In the U.S., approximately 34 percent of adults over
the age of 20 meet the criteria of metabolic syndrome,
with higher rates in older groups than younger groups. 6
Important for those who are overweight or obese, the
prevalence of the risk factors which define metabolic
syndrome increase as BMI increases. Among groups
who are underweight or normal weight, only 7 percent
of men are classified as having metabolic syndrome,
Table 1 – Categorization of Risk: BMI, Waist Circumference, Body Fat
BMI
Waist Circumference
Waist Circumference
(Women)
(Men)
<18.5 < 35 Acceptable
< 40 Acceptable
Underweight
Body Fat
(Women)
Body Fat
(Men)
10 - 13%
Essential Fat
2 - 5%
Essential Fat
14 - 20% Athlete
6 - 13% Athlete
25 – 29.9
Overweight
21 - 24% Fitness
14 - 17% Fitness
30 – 34.9
Obesity, Class I
25 - 31% Average
18 - 24% Average
35 – 39.9
Obesity, Class II
> 32% Obese
> 25% Obese
18.5 – 24.9
> 35 Increased Risk
> 40 Increased Risk
Healthy Weight
> 40
Obesity, Class III
while overweight males were six times more likely and
obese males were 32 times more likely to receive this
diagnosis. Similarly, only 9 percent of females in the
underweight category met the criteria for metabolic syndrome, while women in the overweight category were
5.5 times and obese women 17 times more likely than
normal weight peers to meet criteria. As you can see,
being overweight or obese dramatically increases your
chance of developing metabolic syndrome.
What is metabolic syndrome?
Metabolic Syndrome is diagnosed when someone
has 3 or more of the following:
>Waist circumference over 40 inches for men and 35 inches for women
>Serum triglycerides of 150 mg/dL or higher
>High density lipoproteins (HDL) levels below
40 mg/dL in men or 50 mg/dL in women
>Blood pressure over 130/85 mm Hg
>Fasting glucose of more than 100 mg/dL
Cardiovascular disease (CVD) is considered to be any
disease of the heart and includes coronary heart disease,
stroke, and high blood pressure. One in three adults
has some form of CVD, according to the American
Heart Association. CVD is the leading cause of death in
the U.S., accounting for more mortality than the three
8
diseases following it on the list (cancer, chronic lower
respiratory disease, and injury). 7 Obesity has been
found to be highly related to or cause a number of risk
factors for heart disease including high blood pressure,
high triglycerides and diabetes.8 Obesity is also an independent risk factor for CVD.9
Hypertension is defined as having an average systolic
blood pressure greater or equal to 140 mmHg or an
average diastolic blood pressure greater or equal to 90
mmHg. It is believed that hypertension is related to obesity because obese individuals retain more sodium and
have more fatty tissue, which in turn increases vascular
resistance, which means the body has to work harder
to get blood to flow. A large international study that
looked at hypertension and obesity in a sample of over
10,000 people found that a 10 kg (or 22 lb.) increase
in weight led to a 3.0 mmHg increase in systolic blood
pressure and a 2.3 mmHg higher diastolic blood pressure.10
Diabetes, particularly type 2 diabetes, is known to be
highly related to obesity and lifestyle factors such as
diet, and results when a body isn’t able to properly
manage blood sugar which leads to high glucose levels.
Insulin is a hormone that regulates how cells manage
glucose. When you eat carbohydrates, your body breaks
down the starches and sugars into glucose, which
becomes the fuel your cells use to operate. Insulin is the
vehicle that carries the sugars into the cells. When there
is not enough insulin in your body or your cells become
resistant to the insulin, the level of glucose in your
blood stream increases. When these levels stay high over
a long period of time, damage can occur to the heart,
nerves, eyes, and kidneys.
According to the Centers for Disease Control and Prevention, there are 25.8 million people in the U.S. with
diabetes and an additional 79 million with pre-diabetes.11 People who have diabetes are two to four times
more likely to have a stroke then people who don’t.
For every BMI unit increase over 22kg/m2 there is a 25
percent increased risk of diabetes.12
Cancer risks have also been found to be related to
obesity. In particular, according to the National Heart,
Lung and Blood Institute, there is convincing evidence
that obesity is related to colon, breast, endometrial, and
gallbladder cancer. For instance, when studies compare
women with a BMI below 22 kg/m2 with women who
have a BMI over 29 kg/m2, the rate of distal colon cancer is double.13
Sleep apnea is the sleep disorder most commonly associated with obesity. Sleep apnea occurs when a person
has periods where their breathing pauses while they are
sleeping. They frequently begin gasping in their sleep as
they try to catch their breath. Sleep apnea often leads
to daytime sleepiness and fatigue as the person doesn’t
get enough rest during the night. Risk for sleep apnea
increases as weight increases, and is particularly common in men with a neck circumference over 17 inches
and women with a neck circumference over 16 inches.14
Sleep apnea is diagnosed through sleep studies where
breathing is monitored while a person sleeps.
Cholesterol is a waxy lipid substance that serves a number of functions in the body including: insulating neurons, repairing cells, building cell walls, producing bile,
starting the synthesis of hormones (e.g. testosterone,
estrogen, DHEA, cortisol), and metabolization of fatsoluble vitamins. Cholesterol is critical to the health of
the human body and is not the evil substance which we
have sometimes been led to believe. Despite conventional wisdom, recent studies suggest that dietary cholesterol is not directly related to the amount of cholesterol
in your arteries, and the amount of cholesterol in your
diet is largely unrelated to your risk for obesity or heart
disease. (See the notes section for more information).
Cholesterol, along with triglycerides and other fats, is
transported through your body by lipoproteins, which
are spherical fat molecules with water soluble pro-
9
teins wrapped around them. There are several types
of lipoprotein, including high density (HDL), low
density (LDL), and Very Low Density (VLDL) lipoproteins. Studies have demonstrated that heart disease risk
is related to certain types of lipoproteins as opposed to
total cholesterol levels. Higher levels of LDL particles
increase risk, whereas higher HDL cholesterol levels appear to decrease risk.
Diets which help prevent obesity, those high in healthy
meats, vegetables, fruits, nuts, and seeds, combat the
process which leads to atherosclerosis (hardening of
the arteries). A healthy diet promotes the production
of HDL, which gathers small, dense LDL and oxidized
cholesterol that become stuck in artery walls and sends
them back to the liver for recycling. Low carbohydrate
diets and exercise, two factors which have shown to be
associated with healthy body composition, also raise
levels of HDL. Diets which raise triglycerides appear
to suppress HDL production. Thus, among the most
important components of a blood test for “cholesterol
levels” (remember, it isn’t total cholesterol that is important) are HDL (which you want to be higher) and Triglycerides (which you want to be lower) levels. Overall
LDL levels are less informative, unless your physician
has access to a lab which can separate out small, dense
LDL. Other LDL components appear to be harmless,
which is why a large percentage of people who have
heart attacks also have relatively low LDL levels. (See
Notes section for more information about cholesterol).
Economic Costs of Obesity in the United States
As the prevalence of obesity has continued to increase
over the last several decades in the United States and
worldwide, so have the costs to the people who suffer
from weight problems, their families, and to employers.
The economic costs related to obesity have been estimated based on the direct healthcare costs associated
with treating diseases linked to obesity, such hypertension and diabetes, and the indirect costs, such as lost
productivity.
The direct health care costs of obesity include expenses
(both out-of-pocket and insurance covered) related to
treatment or services provided by a healthcare practitioner for office-based, outpatient, inpatient hospital, or emergency room care and pharmaceuticals or
procedures.15 However, because obesity as a condition
is usually not treated directly, the direct costs of obesity
are estimated based on the cost of treating conditions
related to obesity such as diabetes, heart disease, hypertension, osteoarthritis, sleep apnea, etc.16,17
Studies that estimated the direct costs of obesity all
agree on one thing – the costs are staggering. For
example, Wolf and Colditz conducted the first study
in this area and estimated the direct costs of obesity
to be $45.8 billion in 1990 dollars among all Americans.18 More recent studies such as Finkelstein et al.19
estimated that the direct costs attributable to obesity
among full-time workers to be $30.3 billion dollars (in
2006 dollars) and that individuals with extreme obesity (BMI>35) accounted for 57 percent of those costs.
However, Finkelstein and colleagues also examined the
direct costs of obesity in the U.S. overall and found that
medical cost could be as high as $147 billion dollars per
year.20 Dor and colleagues reviewed a large number of
studies that have been conducted in the United States
over the last 20+ years and concluded that the direct
costs attributable to obesity have substantially increased
over time due to the growing number of people who are
overweight.21
As noted earlier, indirect costs are those that are not
direct medical expenditures, but represent measures
of lost productivity in the workforce. They include
“presenteeism” (where a worker is at work but unable
to perform at their top capacity due to obesity-related
health problems), absenteeism (missed work days or
sick leave), disability and worker’s compensation claims,
and premature death. A number of studies have examined the relationship between obesity and presenteeism
or absenteeism. For example, Tucker and Friedman
found that obese workers were 70 percent more likely
to experience “high-level” absenteeism (seven or more
absences due to illness in the past six months) than lean
employees. Pronk and associates found that obesity was
associated with more lost work days and greater difficulty getting along with co-workers, while greater levels
of physical activity and cardiorespiratory fitness were
associated with higher work quality, job performance,
and greater work quantity in workers from a variety of
occupations.22, 23
Finkelstein et al. evaluated the costs associated with
presenteeism and absenteeism in a sample of over
32,000 full-time workers. Average incremental annual
costs per worker for absenteeism and presenteeism associated with obesity were estimated to be $1,960 and
$5,193 for obese male workers and $1,736 and $5,393
for obese female workers, respectively. This means that
for all workers, obesity is estimated to cost employers
$12.8 billion and $30 billion for productivity losses
associated with absenteeism and presenteeism, respectively.24
Notes
For information about what scientists now think about cholesterol and its role in heart disease, see:
Taubes, G (2008). What’s cholesterol got to do with it? The New York Times, January, 27, 2008. URL:
www.nytimes.com/2008/01/27/opinion/27taubes.html.
Rabbani, N., Godfrey, L., Xue, M., Shaheen, F., Geoffrion, M., Milne, R., Thornalley, PJ. (2011). Glycation of LDL by Methylglyoxal increases arterial atherogenicity: A possible contributor to increased risk of cardiovascular disease in diabetes. Diabetes;
DOI: 10.2337/db11-0085.
For an easy-to-understand review of the Rabbani article see “Super-sticky, ‘ultra-bad’ cholesterol revealed in people at high risk
for heart disease” in Science Daily; URL: www.sciencedaily.com/releases/2011/05/110526204953.htm
References
10
1
Flagel KM, Carroll MD, Odgen CL, Curtin LR. Prevalence and trends in obesity among US adults, 1999-2008. JAMA. 2010;303: 235-241.
2
Flagel KM, Graubard BI, Williamson DF, Gail MH. Excess deaths associated with underweight, overweight, and obesity. JAMA 2005 Apr 20;293(15):1861-7.
3
Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults--The Evidence Report. National Institutes of Health. Obes Res 1998 Sep;6 Suppl 2:51S-209S.
4
World Health Organization. Physical status: The use and interpretation of anthropometry. Geneva, Switzerland: World Health Organization 1995. WHO Technical Report Series.
5
Executive summary of the third report on the National Cholesterol Education Program (NCEP) expert panel on detection, evaluation and treatment of high blood cholesterol in adults. JAMA. 2001; 285:2486-2497.
6 Ervin RB. Prevalence of Metabolic Syndrome among adults 20 years of age and over by sex, age, race, and ethnicity and body mass index: United States. National Health Statistics Report. 13: 2009. CDC: Washington, DC.
7
AHA Heart Disease and Stroke Statistics 2008 Update. Circulation 2008;117:e25-e146.
8 National Heart Lung and Blood Institute (NHLBI). Clinical Guidelines on the Identification, Evaluation and Treatment of Overweight and Obesity in Adults: The Evidence Report. 1998. NHLBI; Bethesda, MD. Report No. 98-4083.
9
Hubert HB, Feinleib M, McNamara PM, Catelli WP. Obesity as an independent risk factor for cardiovascular disease: A 26 year follow-up of participants in the Framingham Heart Study. Circulation. 1983; 67:968-977.
10 Schmieder, RE, Messerli, FH. Does obesity influence early target organ damage in hypertensive patients? Circulation 1993; 87:1482.
11 CDC. 2011 National Diabetes Fact Sheet. 2011. Accessed 1 Jun 2011 from
www.cdc.gov/diabetes/pubs/pdf/ndfs_2011.pdf.
12 Ford ES, Williamson DF, Liu S. Weight change and diabetes incidence: findings from a national cohort of US adults.
Am J Epidemiol. 1997;146:214-222.
13 Giovannucci E, Colditz GA, Stampfer MJ, Willett WC. Physical activity, obesity, and risk of colorectal adenoma in women (United States). Cancer Causes Control.1996;7:253- 263.
14 Davies RJ, Stradling JR. The relationship between neck circumference, radiographic pharyngeal anatomy, and the obstructive sleep apnoea syndrome. Eur Respir J. 1990;3:509-514.
15 Dor A, Ferguson C, Langwith C, Tan E. A heavy burden: The individual costs of being overweight an obese in the United States (Research Report). Washington, D.C.: The George Washington School of Public Health and Health Services, 2010.
16 Popkin BM, Kim S, Rusev ER, Du S, Zizza C. Measuring the full economic costs of diet, physical activity, and obesity-related chronic diseases. Obesity Reviews 2006;7:271-293.
17 Withrow D, Alter DA. The economic burden of obesity worldwide: A systematic review of the direct costs of obesity. Obesity Reviews 2011;12:131-141.
18 Wolf AM, Colditz GA. The cost of obesity: The US perspective. Pharmacoeconomics 1994;5(Suppl 1):34-37.
19 Finkelstein EA, DiBonaventura MD, Burgess SM, Hale BC. The costs obesity in the workplace. JOEM 2010;52:971-976
20 Finkelstein EA, Trogdon JG, Cohen JW, Dietz W. Annual medical spending attributable to obesity: Payer- and service-specific estimates. Health Affairs 2009;28:w822-w831.
21 Dor A, Ferguson C, Langwith C, Tan E.
22 Tucker LA, Friedman. Obesity and absenteeism: An epidemiologic study of 10,825 employed adults. Am J Health Promotion 1998;12:202-207.
23 Pronk NP, Martinson B, Kessler RC, Beck AL, Simon GE, Wang P. The association between work performance and physical activity, cardiorespiratory fitness, and obesity. J Occup Environ Med 2004;46:19-25.
24 Finkelstein
11
Chapter 2
Weight Gain I Disease Risk I Physical Fitness I Body Fat I Hypertension I Healthcare Costs
Chapter 2 Obesity in the Fire Service
How Common is Obesity in the Fire Service?
Not unlike the nation at large, firefighters are struggling
with their body weight and physical fitness. Scientists
have recently looked at the body composition of both
career and volunteer firefighters across the nation, and
the trends are troubling. Rates of overweight and obesity range from 73 percent to 88 percent, depending on
the study.1-10 Rates of clinical obesity among firefighters
have been determined to be between 30 percent and 40
percent, rates similar to the general American public.
The rates of overweight and obesity in the general public are considered alarmingly high; firefighters should
not be mimicking these trends given the dangerous and
strenuous nature of their work.
Skepticism as to whether BMI is a valid measure of
obesity in firefighters has led some to question if the
obesity rates found in the fire service are accurate. Skeptics point out that very muscular firefighters may have a
high BMI but low body fat and be incorrectly labeled as
obese. This concern has not held up when evaluated in
scientific studies. For example, the team at the National
Development and Research Institutes evaluated rates of
misclassification of obesity status based on three body
composition measures in firefighters including BMI,
waist circumference, and measured body fat percentage.
The evaluation found that BMI was an accurate way of
classifying the weigh status of firefighters when compared to other, more clinical-based measures.
Research also shows that many firefighters are not
physically fit. With respect to fitness levels and the
relationship between obesity and fitness, Donovan and
colleagues found that 25 percent of the firefighters in
their study did not meet the minimal fitness threshold
suggested by NFPA 1582 and that, as a result, the firefighters were suffering from a number of metabolic syndrome symptoms.2,11 In a large study funded by FEMA’s
Assistance to Firefighters Grant program, the National
Development and Research Institutes discovered that
over 90 percent of obese career and volunteer firefighters failed to meet even minimal standards of fitness.
As firefighters gain more weight, research has found
that cardiorespiratory fitness plummets and the risk
of cardiovascular disease increases.7 There is solid
evidence that suggests physical fitness is related to job
performance and the performance of simulated firefighting tasks (e.g., hose and ladder carry, donning SCBA,
climbing three flights of stairs, rescue and body drag,
etc.). The fact that so many firefighters are not fit is
13
troubling.12-14 This situation may be at least partially
due to lack of agreement over fitness and body composition standards in the fire service and the fact that
few departments engage in regular monitoring of body
composition and physical fitness in their firefighters.2
Weight Gain Among Firefighters
Many firefighters experience dangerous increases in
body fat throughout their fire service career. One study
found that from 1996/1997 to 2001, the rate of obesity
in their firefighters increased from 33.7 percent to 40.4
percent, a 1.15 pound per year increase over the course
of five years.9 Other studies have found that firefighters
gain an average of about 3.4 pounds each year.15 This
level of weight gain may not sound problematic, but
one must remember that over the typical fire service
career span of 25 years this constitutes a weight gain
between approximately 29 to 85 pounds. That is a lot
of extra weight to haul up a ladder!
Several factors may increase a firefighter’s risk for
weight gain and obesity. First, firefighters engage in
shift work and may develop unhealthy diets or eating
patterns structured around responding to emergencies. Shift work has been associated with weight gain
and obesity risk, and it has been suggested that eating
patterns may be negatively impacted by chronic sleep
deprivation and irregular meal times.16-18 Shift work and
sleep disruption also may interrupt or interfere with
regular physical activity, both on and off duty.17 In addition, research has shown that most firefighters engage
in less than 150 minutes of moderate or greater aerobic
activity per week – the minimum amount recommended
by public health guidelines for all adult Americans. This
amount of activity is lower than what should be expected for firefighters to be prepared to carry out their
rigorous and physically-demanding duties.19
There are no nationally-enforced fitness or physical
activity requirements for firefighters, which may lead to
inconsistent physical fitness training within fire departments, substandard fitness levels, and greater obesity
risk among firefighters.2,4,7 For example, the National
Development and Research Institutes found that only
38.7 percent of career and 23.6 percent of volunteer
firefighters met the fitness threshold suggested by NFPA
1582.4,11 Finally, firefighting is a stressful job and it has
been characterized as a high demand but low control
profession.17 A number of studies have found positive
associations between job strain/stress and increasing
obesity.16-17
Impact and Costs of Obesity to the Fire Service
The epidemic of obesity among firefighters is one of the
most critical issues facing the fire service because it is
associated with disease and a decreased ability to do the
job. In addition, obese firefighters cost more healthcare
dollars, miss more days of duty, and have a greater risk
of disability.
Increased Disease Risk
Given how many firefighters struggle with their weight,
it is no surprise that firefighters suffer from a high rate
of diseases related to obesity and low fitness. Heart
attack is the leading cause of firefighter line-of-duty
death, accounting for about half of all firefighter deaths
each year.20 This rate is substantially higher than those
found for police (22 percent), other emergency medical
service providers (11 percent), and on-the-job deaths for
all occupations (15 percent).20-21 A number of studies
have examined obesity-related heart disease risk factors
among firefighters and have found strong links between
medical issues such as hypertension and unhealthy
cholesterol and increasing BMI.6 Evidence also suggests
that firefighters with high BMIs have greater arterial
stiffness, where the artery walls begin to fray because of
mechanical stress.22 Arterial stiffness puts firefighters at
risk for heart attacks and stroke.
When obese firefighters are compared to firefighters of a
normal weight, a large number of troubling differences
are apparent.4, 9, 23-24 Obese firefighters are much more
likely to suffer from the following:
>Hypertension
>Low HDL (good) cholesterol
>High low-dense LDL (bad) cholesterol
>High triglycerides
>Significant yearly weight gain
>Lower cardiorespiratory fitness
>Reduced muscular strength
>More frequent fatal cardiac events
It seems obvious that being overweight and/or obese
results in substantial suffering for firefighters.
Increased Healthcare Costs
Researchers have only recently begun studying the
impact obesity has had on missing work and increased
healthcare costs among firefighters; however, the few
studies that have been conducted provide bad news
about the costs of obesity in the fire service. Researchers
14
at Harvard Medical School found that firefighters who
received a heart presumption retirement (retiring with
the assistance of disability awards due to cardiovascular
conditions and diseases) in Massachusetts were more
likely to be obese than a comparison group of active
firefighters.25
Soteriades and his team prospectively evaluated CVD
and risk of any type of short-term or permanent disability in a group of 358 male firefighters over more than
six years and reported several interesting findings.8 First,
they found that the percentage of the firefighters who
were obese increased from 33.7 percent to 40.4 percent.
Next, they found that obesity predicted which firefighters would receive disability; each BMI unit increase was
associated with a 5 percent increase in the likelihood
a firefighters would be disabled. This could be particularly problematic for volunteers since their disability
benefits vary from state-to-state. In some cases the state
itself does not offer these benefits, but instead mandates
departments to provide coverage.
National Development and Research Institutes examined the relationship between obesity and missed work
days due to injury in a large group of male, career
firefighters in the Midwestern U.S.26 Obese firefighters
missed between 2.7 and 5 times (depending on how
obese they were) the number of days due to a work injury compared to normal weight firefighters, even when
adjustments were made for things that could potentially
confound the relationship between weight and lost time
at work. Next, the economic costs of absenteeism for
firefighters who were at increasing levels of overweight
and obesity compared to normal weight firefighters was
determined. Compared to normal weight firefighters, the
additional costs to departments because of the greater
missed days of work after injury in firefighters who
were overweight, class I obese, and class II and III obese
over the last year were estimated to be $74.41, $254.00,
and $1,682.9 per firefighter, respectively.26 For volunteers, obesity can result in inadequate staffing from
members missing shifts due to injury or poor health.
Current Efforts to Address Obesity in the Fire
Service
While there are not currently any programs directly
focused on weight loss for the fire service, there are
several programs that focus on improving health and
wellness in a general sense.
NFPA Standards
Two NFPA standards exist that are relevant to health
and wellness: NFPA 1583: Standard on Health-Related
Fitness Programs for Fire Department Members and
NFPA 1582: Standard on Comprehensive Occupational
Medical Programs for Fire Departments.27,13
NFPA 1583 provides a guide for departments to set up
fitness programs with the goal of preparing firefighters
to safely and effectively perform their job duties. The
standard recommends designating a fitness coordinator who can serve as the link between the department
members and the department’s occupational medicine
staff or subject matter experts as well as be the coordinator for fitness evaluations. It also discusses the work
of peer fitness trainers (PFTs), who are department
members that receive certification as a trainer and then
can train other members of their department on fitness
and nutrition.
The standard outlines fitness programs as including:
>Exercise prescriptions through work with PFTs
>Education on warm-up exercises and appropriate cool down
>Instruction on aerobic, muscular resistance, and
flexibility exercises
>Appropriate lifting techniques and back health
training
>Instruction on safety and injury prevention
In addition, the standard outlines a health promotion
program that should include information about:
>Risk reduction
>Health maintenance in general
>Education about the importance of fitness
>Occupation injury prevention
>Accident and injury prevention
>Current information about firefighter fatalities
NFPA 1582 provides an outline for departments
focused on developing and implementing medical
screenings for candidates and incumbent firefighters. A
detailed outline presents the components of a comprehensive medical evaluation that fire departments should
complete on an annual basis. Within each body system
or area (e.g. neck, cardiovascular, etc.), conditions are
identified as either Category A conditions that should
preclude firefighters from job duties or Category B conditions which can be allowed as long as the firefighter
15
“…can perform essential job tasks without posing a
significant safety and health risk to themselves, members, or civilians.”13
The standard recommends annual evaluations as well as
evaluation after occupation-related exposures, injuries,
or illnesses as a means of monitoring health and/or
disease. In addition, the standard outlines mandatory
but non-punitive fitness testing for current firefighters
with the intent of helping firefighters monitor their own
abilities. The evaluation outlined in 1582 includes:
>Body composition
>Aerobic capacity
>Grip, leg, and arm strength
>Flexibility
The standard also recommends a process for tracking
health-related fitness data as a means of monitoring
individual and department improvements over time.
NVFC’s Heart-Healthy Firefighter Program
The National Volunteer Fire Council (NVFC) launched
the Heart-Healthy Firefighter Program in 2003 to focus
on improving the cardiovascular health of the fire service through fitness, nutrition, and educational awareness about heart health and the risks facing firefighters.
The program includes a number of components that are
available to both volunteer and career firefighters. The
program web site (www.healthy-firefighter.org) provides
information and resources about heart health, fitness,
nutrition, health behaviors (e.g. occupational risks,
smoking, stress, and alcohol), and starting a health and
wellness program.
In addition to these resources, the program has several
additional components including:
>Heart-Healthy Firefighter booth at national and state trade shows, which includes free health screenings for firefighters and their families as well as information on improving heart health
>The Fired Up for Fitness Challenge, which is a web-
based program to help firefighters develop and track a personal fitness plan
>The Heart-Healthy Firefighter Cookbook and online recipe archive to provide first responders with healthy menu options
>The Heart-Healthy Firefighter Resource Guide, which contains information to start first responders on the path to a heart-healthy lifestyle
>Health and Wellness Advocate program, which trains firefighters to serve as an advocate for health and wellness within their department, establish a success-
ful health and fitness program, and motivate depart-
ment members to get and stay healthy
>The Put it Out smoking cessation program, which provides tools and resources to help first responders
quit smoking as well as resources for families, depart-
ments, and state associations to support smoking
cessation initiatives and develop department no-
smoking policies
>Webinars on a variety of health and wellness topics, including functional exercise, nutrition, developing a department fitness program, heart health, and
smoking cessation
>Motivational tools such as ideas for monthly depart-
ment health challenges, health and wellness tips sheets, and success stories of firefighters who have been able to lose weight, increase their fitness,
improve their health, and serve as examples for other firefighters
>National Firefighter Health Week, which is an annual event to educate the fire service about a variety of health issues that affect first responders and motivate firefighters to take the steps to improve their health and wellness
>Securing Sponsors for Department Health and Well-
ness Programs guide that helps resource-constrained departments identify, reach out to, and follow up with potential sponsors and donors of department health and wellness programs
Mentioned above, the Health and Wellness Advocate
program trains department personnel to act as the
proponent for health and fitness in their department.
Participants learn basic principles behind developing a
sound health and fitness program and how to advocate
for health and wellness in their department and in the
fire service. As Health and Wellness Advocates, they
encourage and motivate their fellow fire and emergency
personnel to adopt heart-healthy behaviors.
The NVFC partnered with ACE-certified instructors
from L&T Health and Fitness, an award-winning fitness
and health management company, to develop the Health
and Wellness Advocate Workshop. The workshop mixes
classroom components with hands-on learning to equip
participants with the tools and knowledge they need to
succeed as a Health and Wellness Advocate. It includes
an overview of fitness and looks at the areas of anatomy, physiology, and biomechanics, which are the build-
16
ing blocks for designing a safe and effective exercise
program. Advocates are given guidance on establishing
health and fitness goals, safety and injury prevention,
exercise and stress management, and how to develop
a safe exercise program utilizing five components of
fitness. Lessons on nutrition, healthy eating, and weight
management are also topics of focus as they relate to
health and wellness.
At the end of the workshop, the Advocates participate
in a demonstration of functional training exercises
which can be easily utilized at the firehouse with minimal equipment. Advocates leave with a workshop curriculum and other resources to assist in improving upon
or beginning a health and wellness program within their
department.
IAFF/IAFC Wellness Fitness Initiative
In 1996, the International Association of Fire Fighters
(IAFF) and the International Association of Fire Chiefs
(IAFC) collaboratively published the first edition of The
Fire Service Joint Labor Management Wellness/Fitness
Initiative (WFI). Now in its 3rd edition, the program
outlines a comprehensive approach departments can
take to address the health and wellness of their members.28 Components of the WFI include medical evaluations, fitness, rehabilitation guidelines, injury prevention, and behavioral health components.
The WFI recommends annual medical evaluations with
a fire service experienced occupational medicine physician. It is suggested that the exam include vital signs
and a systems based evaluation. In particular, due to
the negative health implications of obesity, the WFI
recommends evaluations that include regular assessment
of body composition through skin fold assessment. Additional recommended tests include a full blood panel,
hearing examination, pulmonary function test, ECG,
cardiopulmonary testing, cancer screening, an update to
immunizations, and an infectious disease screening.
The WFI discusses the importance of fitness for firefighters and recommends allotted time for all fire service
personnel. The WFI also provides certification for peer
fitness trainers (PFTs) through the completion of training courses and a certification exam. The model developed by the WFI suggests a Fitness Committee with representatives from labor, management, the department’s
physician, and an exercise specialist to oversee the PFTs
and their work designing and implementing personalized fitness programs for the members. Another role of
the PFTs is to conduct annual fitness evaluations with
incumbent firefighters that are confidential and nonpunitive. The evaluations, according to the WFI, should
include an assessment of body composition, aerobic capacity, strength, and muscular endurance. Nutrition and
the importance of a balanced diet are also highlighted.
lifestyle. For team-centered sessions, one firefighter from
the crew was trained on the intervention and charged
with conducting trainings. For the lifestyle counseling,
trained counselors met with firefighters on an individual
and ongoing basis to illicit behavior change.
The WFI recommends a comprehensive approach to
rehabilitation, including not only medical concerns
but also fitness training, physical therapy, occupational
therapy, and behavioral health. Injury prevention from
the beginning of the firefighter’s career is also identified
as necessary for departments.
While all groups gained weight across the one-year follow-up, those in the intervention conditions gained less
weight then the control group and also reported eating
more vegetables at follow-up then the control group.
The final domain identified by the WFI is the behavioral
health of firefighters. The WFI advocates a comprehensive program be made available to firefighters with
annual screenings performed for all incumbent firefighters. It is recommended that each department work with
a behavioral health specialist to provide services, direct
counseling efforts when necessary, and make appropriate referrals. The use of a department chaplain in times
of crisis and to assist with spiritual needs of the firefighters is also recommended.
The Johns Hopkins Bloomberg School of Public Health
(JHBSPH) partnered with the National Volunteer Fire
Council to conduct a three-year research project with
funding from a FEMA Fire Prevention & Safety Grant.
The study addresses a direct need for effective programs
and policies intended to reduce on-duty deaths among
firefighters, particularly those related to heart disease
and heart attacks.
There have been a limited number of research-based
programs designed and tested in the fire service to
improve firefighter health. Arguably one of the most
notable is the Promoting Healthy Lifestyles: Alternative
Models’ Effects (PHLAME) Firefighter Study.15 The program was designed to encourage fitness, healthy eating,
and healthy body weights among firefighters.
The goals at the outset of the project were to explore
the firefighter culture of fitness and wellness; to identify barriers to and facilitators for health and wellness
among firefighters; and to develop, implement, and evaluate a pilot intervention program that addresses those
health barriers and facilitators. Fifteen focus groups
with a total of 98 firefighters and fire service leaders
were conducted in 2009 to learn about culture, barriers,
and facilitators for health among firefighters. More than
half of the focus group participants identified themselves as overweight (46 percent) or very overweight
(8 percent). When selecting food and beverages, 48 percent of participants reported that they avoid fats (e.g.
trans fats and saturated fats) and 42 percent avoid junk
food. When asked how closely they watch what they eat
for weight control, 52 percent of participants reported
moderately (44 percent) or very closely (8 percent).
The study captured a baseline assessment (questionnaire
and physical testing) of the participants at the beginning of the study and then repeated the tests at one year.
During the study, the participants were divided into the
following two treatment interventions and a control
group: (1) team centered, peer led trainings, (2) individual lifestyle counseling with motivational interviewing, and (3) a control group who only received their test
results with a brief explanation and listing of normal
values. Participants in the two interventions received
the PHLAME manual with information on physical
activity, nutrition, and health conditions affected by
This information was then used to develop, implement,
and evaluate a pilot diet and nutrition intervention
program to reduce cardiac risk factors among firefighters. Eight fire stations in Maryland were enrolled in the
pilot intervention program; with two stations serving
as the control group (these stations will receive the
intervention program at the end of the study). Those in
the intervention group received five monthly education
sessions on nutritional topics such as fats, sugar, whole
grains, and portion sizes that included cooking demonstrations, books, handouts, posters and other resources
related to healthy eating and creating a healthy eating
As part of its WFI efforts, the IAFF hosts the Fit to Survive web site (www.iaff.org/hs/fts/ftsdefault.asp) which
provides health tips for firefighters, as well as resources
such as a menu planner, healthy food choices when eating fast food, information controlling blood pressure,
and tools for smoking cessation.
PHLAME Firefighter Study
17
Firefighters and Wellness: Building a Healthy Future
Through Partnership and Science
environment. Half of the intervention stations had twothree firefighters trained by the Johns Hopkins Weight
Management Center to be peer advocates for health
and nutrition. Discounts at local eateries for healthier
menu items were offered, and information on healthier
vending machine items, local area farmers markets, and
community supported agriculture programs were provided to increase access to healthier foods. Additionally,
a “Biggest Loser” type of competition was held between
fire stations.
The pilot intervention program was implemented
from December 2010 through June 2011, and the data
collected includes weight, body fat percentage, waist
circumference, BMI and blood pressure at baseline,
two months and six months as well as cholesterol and
glucose at baseline and at six months. Firefighters filled
out surveys at different times throughout the process,
answering questions regarding diet, exercise, alcohol,
smoking, stress and nutrition knowledge among others.
Final results will be collected in December 2011 (six
months post intervention). The data is currently being
analyzed.
References
1
Mancuso J. Overweight and obesity on the Omaha Fire Department. Emmitsburg, MD: National Fire Academy; 2003.
2
Donovan R, Nelson T, Peel J, Lipsey T, Voyles W, Israel RG. Cardiorespiratory fitness and the metabolic syndrome in
firefighters. Occup Med (Lond). 2009;59:487-492.
3
Tsismenakis AJ, Christophi, CA, Burress JW, Kinney AM, Kim M, Kales SN. The obesity epidemic and future emergency responders. Obesity 2009;17:1648-1649.
4
Poston, W.S.C., Haddock, C.K., Jahnke, S.A., Jitnarin, N., Tuley, B.C., & Kales, S.N. (2011). The prevalence of overweight, obesity, and substandard fitness in a population-based firefighter cohort. Journal of Occupational and Environmental
Medicine, 53, 266-274.
5
Clark S, Rene A, Theurer WM, Marschall M. Association between body mass index and health status in firefighters. J Occup Environ Med 2002;44:940-946.
6
Kales SN, Polyhronopoulos GN, Aldrich JM, Leitao EO, Christiani DC. Correlates of body mass index in hazardous
materials firefighters. J Occup Environ Med 1999;41:589-595.
7
Durand G, Tsismenakis AJ, Jahnke SA, Baur DM, Christophi CA, Kales SA. Firefighters physical activity: Relation to fitness and cardiovascular disease risk. Medicine & Science in Sports & Exercise In press.
8
Soteriades ES, Hauser R, Kawachi I, Christiani DC, Kales SN. Obesity and risk of job disability in male firefighters. Occup Med (Lond). 2008;58:245-250.
9
Soteriades ES, Hauser R, Kawachi I, Liarokapis D, Christiani DC, Kales SN. Obesity and cardiovascular disease risk factors in firefighters: A prospective cohort study. Obes Res. 2005;13:1756-1763.
10 Yoo HL, Franke WD. Prevalence of cardiovascular disease risk factors in volunteer firefighters. Journal of Occupational and Environmental Medicine 2009;51:958-962.
11 National Fire Protection Association (NFPA). NFPA 1582, Standards on comprehensive occupational medicine programs for fire departments. Quincy, MA: NFPA, 2006.
12 Elsner KL, Kolkhorst FW. Metabolic demands of simulated firefighting tasks. Ergonomics. 2008;51:1418-1425.
13 Michaelides MA, Parpa KM, Thompson J, Brown B. Predicting performance on firefighter’s ability test from fitness
parameters. Res Q Exerc Sport. 2008;79:468-475.
14 Rhea MR, Alvar BA, Gray R. Physical fitness and job performance of firefighters. J Strength Cond Res. 2004;18:348-352.
15 Elliot DL, Goldberg L, Kuehl KS, Moe EL, Breger RKR, Pickering MA. The PHLAME (Promoting Healthy Lifestyles:
Alternative Models’ Effects) firefighter study: Outcomes of two models of behavior change. Journal of Occupational and Environmental Medicine 2007;49:204.213.
16 Schulte PA, Wagner GR, Ostry A, et al. Work, obesity, and occupational safety and health. Am J Public Health 2007;97:
428-436.
18
17 Kales SN, Tsismenakis AJ, Zhang C, et al. Blood pressure in firefighters, police officers, and other emergency workers. Am J Hypertens 2009;22:11-20.
18 Karlsson B, Knutsson A, Lindahl B. Is there an association between shift work and having a metabolic syndrome? Results from a population based study of 27,485 people. Occup Environ Med 2001;58:747-752.
19 Haskell WL, Lee IM, Pate RR, Powell KE, Blair SN, Franklin BA, Macera CA, Heath GW, Thompson PD, Bauman A.
Physical activity and public health: Updated recommendation for adults from the American College of Sports Medicine and the American Heart Association. Medicine & Science in Sports & Exercise 2007;39:1423-1434.
20 Centers for Disease Control and Prevention. Fatalities among volunteer and career firefighters – United States, 1994-2004. MMWR Morb Mortal Wkly Rep. 2006;55:453-455.
21 Maguire BJ, Hunting KL, Smith GS, Levick NR. Occupational fatalities in emergency medical services: A hidden crisis. Ann Emerg Med. 2002;40:625-632.
22 Fahs CA, Smith DL, Horn GP, et al. Impact of excess body weight on arterial structure, function, and blood pressure in
firefighters. Am J Cardiol. 2009;104:1441-1445.
23 Hokanson JE. Hypertriglyceridemia and risk of coronary heart disease. Current Cardiology Reports 2002;4:488-493.
24 Geibe JR, Holder J, Peeples L, Kinney AM, Burress JW, Kales SN. Predictors of on-duty coronary events in male firefighters in the United States. American Journal of Cardiology 2008;101:585-589.
25 Holder JD, Stallings LA, Peeples L, Burress JW, Kales SN. Firefighter heart presumption retirements in Massachusetts 1997-
2004. Journal of Occupational and Environmental Medicine 2006;48:1047-1053.
26 Poston WSC, Jitnarin N, Haddock CK, Jahnke SA, Tuley BC. Obesity and injury-related absenteeism in a population-based firefighter cohort. Obesity In press.
27 National Fire Protection Association (NFPA). (2007). NFPA 1583: Standard on Health Related Fitness Programs for Fire Department Members.
28 International Association of Firefighters (IAFF) (2008). The Fire Service Joint Labor Management Wellness-Fitness Initiative. 3rd ed. Washington, DC.
19
Chapter 3
Why Is There An Epidemic
of Obesity in the Fire Service?
Snacks I Nutrition I Environment I Portion Size I Sugar I Sleep I Processed Carbohydrates
Chapter 3 Why Is There An Epidemic of Obesity in the Fire Service?
Why Obesity Is So Common
There are a number of well-written articles and books
which attempt to explain the rapid rise of obesity in the
U.S. and other industrialized countries (for example,
Cutler et al.).1 This section examines the major contributing factors to obesity in the fire service. The three
areas covered include:
1. The nutrition environment in the firehouse
2. The role of processed carbohydrates and sugar in the diet
3. Work schedules and sleep
“Whether it’s eating, us working together, us playing
together, I think all of that makes us become a better crew together and understand how to deal with
each other.”
Firefighter in the Western U.S.
“When you’re dealing with a group of guys who do a
food kitty, and you say, ‘I’m going to eat on my own.’
That kind of puts a wedge between - it’s like, ‘Oh
what? You don’t want any part of the group?’”
Firefighter in the Central U.S.
Meal times were consistently noted as a way of monitoring the interpersonal relationships of the crew.
In addition, the limitations in the role physical activity
plays with regard to body composition will be examined.
The Nutrition Environment in the Firehouse
There is very little research available about the nutrition environment in the fire service. In order to better
understand food choices, eating habits, and opinions
about nutrition among firefighters, the National Development and Research Institutes conducted a qualitative
study funded by the American Heart Association (the
Heart Healthy Heroes Study) that included, among
other health topics, a focus on the firehouse nutrition
environment.2
For the study, interviews and focus groups were held
with firefighters, fire chiefs, medical directors, and
health promotion personnel from 34 fire departments
across the country.3 Questions ranged from broad (e.g.,
“What do you consider the biggest health challenges in
the fire service?”) to specific questions on various health
topics (e.g., nutrition, physical activity, mental health).
All interviews and focus groups were recorded and transcribed. Using scientific methods for textual analysis,
the following major themes emerged.
“I kind of can tell the climate of the station, whether
if it’s good or bad, by how they cook.”
Fire Chief in the Western U.S.
“But you go to the stations and they’re eating out a
lot or they’re eating out of cans, usually something –
something’s going on.”
“You know, they have problems in their groups and
they don’t seem to cook up as much. Just like guys
that don’t get along together.”
“In the fire service here in the city, those who eat
together, stay together.”
Food choices and preparation were points of pride for
several firefighters who reported that preparing good
meals was a form of bonding and caring for their crew
members.
“I had a disastrous meal the other day. We were supposed to eat burgers, they turned out Sloppy Joe’s
– it was embarrassing. I was truly ashamed of that
meal.”
Bonding Over Meals
One of the most consistent findings was that food decisions and the nutrition environment in the firehouse
were as much about bonding as nutrient intake. Firefighters and chiefs consistently reported that meal times
are a time for bonding and building relationships. Often, meal times were referred to as “family time” for the
crews. Some representative examples of the statements
made by firefighters include:
“You want to eat with your family at home, so you
eat with your family at work.”
21
Portion Size
A common topic related to healthy eating in the firehouse was portion size. While the portion size of some
foods, like vegetables, may not have a negative effect on
body composition and health (it’s hard to eat too much
broccoli!), foods identified as being served in high quantity were often high carbohydrate and high sugar foods.
“Give me a plate with spaghetti. I want a plate full of
spaghetti type things.”
Firefighter in the Eastern U.S.
“[It’s a] competitive eating club. You know, where
everybody wants to get their share.”
“Trying to get a meal that fills you up for three bucks
is not necessarily as healthy of a meal if you spent
another couple extra bucks and got organic stuff –
the healthier stuff is not the least expensive stuff.”
Several firefighters also discussed the challenge of not
knowing what the day would bring and how that contributed to eating larger meals as a way to counteract
hunger throughout the day.
“I think that’s why, in some cases, we overeat –
because you might get a meal this morning and be
gone the whole day.”
“Speaking specifically of the fire department –
there’s a sense that we could be called out for many
hours so people don’t want to short themselves like
they could do at home.”
Both volunteer and career firefighters discussed the challenges of finding time to cook and eat healthy meals.
Many discussed the unpredictability of emergency calls
as a unique challenge, stating that they tend to eat when
they can and choose foods that are convenient rather
than healthy.
“You eat when it’s convenient and not necessarily
when it’s the best thing for you. And nine times out
of ten you’re eating when you can.”
Meal Planning
In firehouses across the country, firefighters talked about
the challenge of meal planning within a budget and how
meal decisions were often made based on cost at the local grocery store that day. Several indicated that cost led
to decisions to choose less healthy options.
“It’s quantity over quality sometimes. So, you can
make a lot of spaghetti with garlic bread and stuff
like that for pretty cheap.”
“What they’re going to do is they’re going to look at
the ads and see what’s on sale and how they can get
the most from the money that they have.”
Chief in the Eastern U.S.
“The cost of the groceries decides the menu that
day. We try to see what’s on sale.”
Firefighter from the Western U.S.
22
“A lot of lasagna, spaghetti, Sloppy Joes, and French
fries….That’s the stuff that, you know, goes a long
way.”
Eating at the Firehouse
There were mixed reports on the types of food firefighters eat on duty or at the firehouse compared to their
home eating habits. Some reported that they eat better
at the fire station because the schedule allows more
thoughtful meal planning. Others discussed the positive
impact of crew level decisions to eat healthy. On the
other hand, many firefighters reported that they eat less
healthy at the firehouse, particularly during slow periods when there is more time for cooking. One firefighter
remarked, “If I’m going to have a really unhealthy meal,
this is where I’m going to have it.”
Peer Pressure
Several personnel discussed peer pressure at the firehouse. At times, firefighters discussed trends toward
healthier eating as being a positive influence on their
own eating habits. On the other hand, some discussed
the difficulty with suggesting healthier alternatives
and stated that, particularly for new recruits, having a
different opinion about food and refusing to eat with
everyone is difficult and could be viewed as not wanting
to be a part of the crew.
“If you’re working with that crew, it can be difficult
if you’re at the lower rank to eat healthy unless you
bring your own meal, but then you’re kind of an outcast for doing that.”
“If the crew has an attitude of eating healthy, then
everyone tends to follow along that same path. If
the crew attitude or mentality is every meal that
we have in our shift is going to be at McDonalds or
Jack in the Box, or whatever, then it’s very difficult,
particularly for younger firefighters, to buck that
mentality.”
Snacking
Snacking was identified as a particular challenge at the
firehouse. Having an abundance of high sugar or high
carbohydrate snacks around the firehouse was consistently reported as being a big challenge.
“You have that downtime, you know, and it’s easier
to have M&Ms, a Snickers bar in the firehouse than
it is to have a carrot or celery.”
Another challenge is the number of treats and desserts
available at the firehouse from community members.
“What kills us sometimes is during, like, holidays or
like, 9/11, families around the fire station bring in
food. And they mean the best intentions, but they
bring in the worst food for you – cookies, cake, and
stuff.”
Firefighters in the Eastern U.S.
Making Changes
There were mixed opinions about firefighters who
wanted to improve their health through better eating.
While some crews indicated they were open to changes,
many said that recommending major dietary changes
was seen as inflammatory and was, at times, taken
personally.
“When everybody is eating together, and all of a
sudden somebody decides, ‘Man, I know I shouldn’t
be doing that, but how am I going to tell them I
don’t want to eat biscuits and gravy? I want to have
oatmeal, or cereal.’ You know you’re going to take a
little bit of ribbing. You bite the bullet and do it if you
really feel like you have to.”
Traditions
Another common theme focused on the “traditions”
associated with eating at the firehouse. A number of
firefighters discussed how ingrained food traditions
served as a difficult barrier to improving diet. While the
particular traditions varied by region and department,
several crews around the country had rules, traditions,
or social norms with buying desserts – often ice cream
or donuts – based on different activities. For example,
in several cases new recruits were expected to bring
donuts when they started working with a new crew.
Purchasing ice cream or cake for fellow crew members
often served as a “punishment” for mistakes, accidents,
or poor performance.
23
“You hit a curb, you lose a game, you do something
stupid, and you owe ice cream.”
Moving Towards Healthier Food Choices
Several crews reported trends within their departments
toward healthier food choices. Many were convinced
that firefighters are working toward better health.
“Guys are starting to look at their diet a little bit
more. And so we’re more health conscious.”
Volunteer Firefighters
Volunteer firefighters often discussed challenges associated with healthy eating that were unique to their situation. For example, many volunteer firefighters referenced time demands as a factor in limiting their ability
to prepare healthy meals.
“The paid people have time to work out and, you
know, they hopefully are cooking properly. But we
don’t have that set up here. You’re on your own, you
do your own thing, and you fly by the seat of your
pants. You don’t have a set schedule of workout
times or shopping for proper groceries.”
“You’re not going to sit there and say, ‘Well, somebody will take that call. We’ll have a nice dinner.’ It’s
not going to happen.”
While some volunteer firefighters discussed eating at
the firehouse on a regular basis, many others said they
didn’t spend any extra time at the fire station because
their volunteer activities already consumed a great deal
of their time.
In summary, the challenges facing firefighters with
regard to healthy eating habits include pressures to
purchase inexpensive foods and consume large portions,
the temptations of unhealthy snacks at the firehouse,
and peer pressure. Despite these challenges, there also
appears to be some evidence of an increased awareness
of the need for firefighters to have a healthy diet and to
support quality food choices.
Processed Carbohydrates and Sugar
For the past several decades the scientific community
and government bodies have provided a simple, consistent message about how to manipulate diet to be
lean and healthy: lower dietary fat intake and consume
fewer calories. Health promotion messages encouraged
the consumption of fewer calories from fats for foods
such as meat, eggs, and butter and more calories from
vegetables, fruits, and grains including wheat and corn.
The most recent version of the United States Department of Agriculture (USDA) Nutrition Guidelines (see
www.choosemyplate.gov/) continues to promote the
message that your diet should primarily come from
carbohydrates, including a large amount of grains, and
to limit fat intake. For the most part, Americans have
dutifully followed these dietary recommendations. According to the Centers for Disease Control and Prevention, during the period from 1971 to 2000, the amount
of calories in our diet that comes from fat decreased in
the American diet, although the overall caloric intake
increased slightly; however, this increase appears to be
due to consuming more carbohydrates.4
Given the health messages promoted over the past
several decades, it is not surprising that Americans are
now ingesting more carbohydrates and, in particular,
have dramatically increased the amount of processed
carbohydrates and sugar they consume. Until recently,
if you went to a medical practitioner or diet center for
help losing weight, they would inevitably suggest that
you eat a low-fat, high carbohydrate, low-calorie diet.
A barrage of low-fat products was created by the food
industry, from low-fat cookies to low-fat hamburgers.
This morning, many well-intentioned parents served
their children (and some firefighters served themselves)
a “healthy” breakfast consisting of Honey Nut Cheerios
or some other processed, sugar-sweetened, yet “whole
grain” cereal and skim milk. One serving (3/4 cup – but
who actually only eats 3/4 cup of cereal?) of Honey Nut
Cheerios provides 22 grams of carbohydrates and only
2 grams of protein and 1.5 grams of fat. If you read the
side of the box, you will notice that the second, fourth,
and fifth ingredients are added sugars. Adding skim
milk to your bowl will add another 12.3 grams of carbs
(in 1 cup) and only 8.7 grams of protein (a single egg
provides 12.6 grams of protein). Not to worry, the cereal box reassures you that eating what tastes curiously
like a dessert is heart healthy. Your great-grandparents
would make a funny face if they looked at this breakfast
– it probably would not even look like food to them. In
1977, the average person consumed about 122 pounds
of refined sugar per year (already way too much) – by
2000 that total had risen to nearly 154 pounds!
In fact, 75 percent of all the calories we now consume
are in the form of highly processed foods, mostly
packed with carbohydrates.5
24
Why Conventional Diets Fail
The result of Americans reducing the amount of fat they
eat and consuming more carbohydrates, particularly
from refined grains and sugar, has been a rapid increase
in the prevalence of obesity and metabolic disorders. It
is not unusual for a firefighter to eat over 300 grams of
carbohydrates per day (one Einstein bagel has over 70
grams of carbohydrates; one medium Coke at McDonalds has 86 grams). This has likely contributed to an
epidemic of obesity in the fire service. Ironically, the
“fats are evil, carbs are good” claim has never been
proven, and a growing body of scientific data now suggests that is it misguided. Even leading scientists writing
in the Journal of the American Dietetic Association, the
flagship journal for our country’s dietitians, are admitting that the war on dietary fat was likely a mistake.6 So
why were we told that fat intake was responsible for us
getting fat and out of shape?
The story of how “fat is bad” became conventional
wisdom and continues to be propagated is probably
best told in the bestselling book Good Calories, Bad
Calories, by science writer Gary Taubes.7 In short, a
dynamic and highly eloquent scientist working at the
University of Minnesota named Ancel Keys promoted
the hypothesis that eating fats, particularly saturated
fats from animal products, leads to higher cholesterol
levels and ultimately to heart disease. This hypothesis
was based on several “facts” that have now been called
into question, including the claim that countries where
fat intake is low have lower rates of heart disease than
countries where fat intake is high, and that heart disease
was rare until the 1920’s when Americans shifted their
diets from plant-based foods to animal foods which
were high in fat.
The U.S. government adopted Keys’ hypothesis as their
official view on diet and ever since has set out to both
prove its basic tenants (through government-funded
research) and to change the eating habits of Americans.
Dietary recommendations are influenced by a number of interests, not just the science of nutrition, and
conventional wisdom is difficult to change.8 However, a
large chorus of respected scientific studies now question the conventional wisdom and our understanding of
what constitutes a “healthy diet” is in transition. A few
examples:
>The Framingham Heart Study failed to support key elements of Keys’ hypothesis. It found no relationship between dietary cholesterol and blood cholesterol and participants who ate the most saturated and total fat
weighed the least and were the most physically
active.9
>The Multiple Risk Factor Intervention Trial, one of
the largest human trials ever conducted with a stag-
gering cost of $115 million, had participants in their intervention cut dietary cholesterol, saturated fats, and total calories. The study found no significant impact on coronary heart disease or total mortality.10
>The largest randomized trials of women to date, the Women’s Health Initiative, randomly assigned over 48,000 women to either a low-fat diet high in fruits, vegetables, and grains or to general dietary education. At the end of the eight-year intervention, the authors concluded that the low-fat diet did not reduce the risk of coronary heart disease or stroke in women.11
Given the results from these landmark studies, it was
no surprise when researchers reviewed the literature
on obesity interventions for both adults and children
and found disappointing results, particularly in the
long-term.12 While large, well-conducted studies were
discovering that low-fat, low-calorie diets were ineffective at improving health in the long-term, scientists
began looking at whether it was wrong to adopt Keys’
assumptions about diet and health. Some of their findings included:
>Processed carbohydrates and sugar were introduced into our diets only recently, and our bodies are health ier without them. Jarod Diamond, a Professor of
Geography and Physiology and author of several bestselling books, wrote extensively about how we
evolved eating a wide variety and wild plants and
animals. Although our bodies still crave this diet, we have replaced it with lower-quality foods that are
easy to produce cheaply: “While farmers concentrate on high-carbohydrate crops like rice and potatoes, the mix of wild plants and animals in the diets of surviv-
ing hunter-gatherers provides more protein and a better balance of other nutrients…The farmers gained cheap calories at the cost of poor nutrition. (Today just three high-carbohydrate plants – wheat, rice, and corn – provide the bulk of the calories consumed by the human species, yet each one is deficient in certain vitamins or amino acids essential to life.)”13
>People from non-industrialized areas often eat diets high in fat and protein and low in carbohydrates, and they are healthier. Anthropological studies find that non-industrial groups such as the residents of the
Tokelau Island or the Inuits consume diets very high in fats, including saturated fats, and do not have high rates of obesity and heart disease. In fact, when
25
residents of the Tokelau Islands migrated to other countries and adopted Westernized diets lower in fat
and higher in carbohydrates, their rate of heart
disease and obesity significantly increased.14
>Compelling research is emerging which challenges the conventional wisdom that fat causes obesity or that saturated fat is a cause of heart disease.15 On the contrary, saturated fat appears to be, at worse, neutral in its impact on our heart while poly-unsaturated fats are heart healthy. A meta-analysis (a mathematical
combination of several individual studies) published in a 2010 issue of American Journal of Clinical Nutri tion found that among almost 350,000 people studied, there was no significant connection between
saturated fat intake and heart or vascular disease.15 Although you may have been told that saturated fat can increase your overall LDL (“bad” cholesterol) levels, you should know that LDL consists of many sub particles. Studies suggest that saturated fat pri-
marily increases large LDL particles (which are widely considered harmless) and not small LDL particles (which are linked to heart disease). On another posi-
tive note, dietary fat intake tends to increase HDL, or good cholesterol.
>Low-carbohydrate diets appear to be effective in
reducing weight and positively impact risk for car-
diovascular disease.16 For example, results from the
A to Z Weight Loss Study published in the Journal of the American Medical Association found that the Atkins diet (which is very low in carbohydrates)
resulted in twice the weight loss of the other diets tested and did a superior job of improving heart disease risk factors. Even when prescribed along with an effective weight loss medication (Orlistat), a low-
fat diet failed to produce better results than a low-
carbohydrate diet which did not include medications.16
>Calorie restriction, which is typically a component of low-fat diets, results in a disproportionate decrease in energy expenditure and metabolism. Thus, weight loss by following a reduced calorie diet can only be maintained by permanent calorie restriction, which has proven to be difficult for most people.
>Clinical trials comparing low-fat diets with low carbohydrate diets generally ask participants in the low-fat group to restrict their total caloric intake (usually 1,500 calories or less for women and 1,800 for men) while those on the low-carbohydrate diet are
not asked to restrict their calories. Even so, the low-
carbohydrate diet generally outperforms the low-fat, low-calorie diet without prescribing that the dieters semi-starve themselves.17
>Low-fat, low-calorie diets, even if effective for weight
loss in the short term, tend to lower HDL (good cholesterol) and result in less fat loss in the trunk region (where body fat is more dangerous) compared to low-carbohydrate diets. In one study, a very low-
carbohydrate diet resulted in three times the body fat loss in the trunk region compared to a low-fat diet.18
Low-carbohydrate diets seem to result in more fat loss and less muscle loss during weight reduction compared to low-fat, calorie-restricted diets.
>High total carbohydrate consumption is related to oxidative stress and can cause inflammation. Reducing
carbohydrates has a more favorable impact on the metabolic condition than a low-fat diet. Low-
carbohydrate diets have even been found to improve attention deficit hyperactivity disorder, autism,
diabetes, and epilepsy.19
The results for low-carbohydrate diets (particularly
diets low in processed carbohydrates and sugar) are so
impressive that two of the most highly regarded scientists in the area of nutrition, Dr. Jeff Volek and Richard
Feinman, concluded that metabolic syndrome could be
defined as “a set of markers that responds to CHO [carbohydrate] restriction.”20 They point out that a reduction in carbohydrates results in lowering fasting glucose,
insulin, triglycerides, and blood pressure and raising
HDL. While there are still plenty of scientists and medical practitioners who continue to advocate low-fat,
low-calorie diets, the tide seems to be turning. Why does
carbohydrate restriction result in these health improvements? The answer partially lies in its role in the regulation of insulin and impact on insulin insensitivity.
Insulin 101 for Firefighters
There are three main macronutrients in the food that
we eat: protein, fat, and carbohydrate. Your body uses
these macronutrients for fuel. If you take in too much
fuel, the body will attempt to store the excess for times
when the fuel might not be readily available. Throughout history there have been times of plenty and times
of famine, so the ability to store fuel was critical to
survival as a species. Insulin plays a critical role in the
body’s ability to store fuel. Understanding the role of
insulin is imperative to adopting a healthy diet.
Insulin’s role in fuel storage was initially discovered
by German scientist Paul Langerhans when he noticed
particular cells in the tissues of the pancreas. These cells
had the appearance of small islands and were therefore
called the islets of Langerhans. These beta cells in the
26
pancreas have the ability to produce insulin. Although
insulin plays an important role in our health, too much
insulin negatively affects the body.
All consumed carbohydrates are eventually converted
to a form of sugar called glucose. Although there are
no “essential carbohydrates,” some carbohydrates are
healthy and will support the active lifestyle of a firefighter. That is why it is best if to choose certain highquality vegetables and some fruits to maximize the
quality and reduce the total amount of carbohydrates in
your diet. For example, 100 grams of raw broccoli has
only 6.6 grams of carbohydrate and is packed with nutrients, while 100 grams of white bread has a whopping
50.6 grams of carbohydrate and is nutritionally anemic
compared to most vegetables. A diet that consists of too
many processed carbohydrates and sugars results in the
body having more glucose than it needs for fuel. This
can become toxic and the body needs a way of getting
the glucose out of the bloodstream.
It is critical to note that carbohydrates largely control
insulin; protein and fat do not produce as much of
an insulin response. The beta cells of your pancreas
monitor the amount of blood glucose in your body, and
when it gets too high, they will secrete insulin. The more
glucose in your body, the more insulin will be secreted
by your pancreas. Insulin allows glucose to be stored in
muscle and liver cells, up to a certain point. Once these
cells are full, the remaining glucose gets converted into
triglycerides in the liver and stored in fat cells.
If the body is forced to deal with too many carbohydrates, the muscle and liver cells respond by being less
responsive to insulin and, as a result, more glucose
remains in the blood stream. In medical terms, they become insulin resistant and stop responding to insulin’s
message to store glucose. The beta cells of the pancreas
notice that there is too much glucose in the blood and
pump out even more insulin, resulting in more triglycerides being stored in fat cells. Bombarding our bodies
with carbohydrates results in an increase of insulin
insensitivity in muscle and liver cells – unless you are
exercising at a very high level like a marathon runner.
Unfortunately, this means fat cells will continue to grow
as they store the excess glucose. Given the high amount
of carbohydrates we are eating, it is not surprising that
obesity is an epidemic!
In time, even our fat cells resist storing more glucose.
When this happens, glucose stays in your blood longer
which signals your pancreas to work harder and harder
to produce more insulin. Eventually, this results in
blood glucose toxicity, chronically high levels of insulin,
and nonfunctioning beta cells. All of this leads to high
levels of inflammation, diabetes, and heart disease.
Chronically high levels of insulin has many negative
effects on the body, including a decreased metabolic
rate, lower testosterone and other sex hormones, lower
energy throughout the day, and reduced cognitive functions. Feed your body lean, high quality meats, vegetables, fruits, nuts, and seeds and it will thank you.
Short-Term Effects of a High-Carbohydrate Meal
Not only can a high-carbohydrate diet lead to poor
long-term health, it will also set a biological rollercoaster into motion leading to hunger, fatigue, and
poor mood. For example, a high-sugar or high-carbohydrate meal for breakfast leads to tiredness and
hunger throughout the day. The body will rapidly break
down the carbohydrates, resulting in a sharp increase
in blood sugar. In response, the pancreas will release a
large amount of insulin and the blood sugar levels will
decrease to the point where three or four hours later
hypoglycemia (low blood sugar) sets in. This process
occurs over and over during the day when following a
low-fat, high carbohydrate meal plan.
In contrast, a meal consisting of a vegetable omelet
and a bowl of blueberries (a balanced amount of fat,
protein, and carbohydrate) stabilizes blood sugar and
insulin levels and prevents the sharp drop in glucose
levels. The fat in the meal will keep the body feeling
full and energetic and will not spike insulin production.
Followers of a diet moderate in carbohydrates coupled
with plenty of healthy fats and protein report feeling
less hungry and more energetic throughout the day.
Glycemic Index
What should we eat if diets high in carbohydrates,
particularly from processed carbohydrates and sugar,
can lead to bad health outcomes? One helpful tool is
to focus on foods with a low glycemic index, which are
typically meats, vegetables, some fruit, nuts, and seeds.21
The glycemic index is a measure of a food’s impact on
blood sugar. Carbohydrates that result in rapid rises in
blood sugar have a high glycemic index (typically foods
like cereals, pasta, bread, chips, and desserts), while
those that break down relatively slowly during digestion
and do not cause blood sugar to sharply increase have
a low glycemic index. The glycemic index is based on
27
giving a score of 100 to glucose, and other foods are depending on a score above or below 100 given their propensity to raise blood sugar relative to glucose. Medical
studies have found that people who concentrate their
diets on foods with low glycemic scores have significantly lower rates of heart disease, diabetes, gallbladder disease, and breast cancer compared to those who
regularly consume foods with a high glycemic index.
A number of lists providing the glycemic index of common foods are readily available on the Internet. Low
glycemic index foods are primarily meats, vegetables,
some fruits, nuts, and seeds, while high glycemic foods
include starches, breads, pasta, rice, potatoes, grains,
and sweets. Eating more low glycemic and less high
glycemic index foods is an easy way to dramatically improve the quality of your diet. The chart below provides
examples of low (GI < 55) and high (GI > 70) glycemic
index foods.
Low Glycemic Foods
Eggs
Tomato
Blueberries
Turkey
Onion
Broccoli
Chicken
Mushrooms
Nuts
Salmon
Spinach
Salsa
Shrimp
Eggplant
Pineapple
Lamp
Asparagus
Cauliflower
Pork
Strawberry
Green beans
Lettuce
Zucchini
Milk, Whole
Apple
Cherries
Peach
High Glycemic Foods
Beets
Bagels
Muffin
Baked Beans
Raisins
Tortillas
French Fries
Biscuit
Potato Chips
Peas
Granola
Ice Cream
Potato
Cereal
Pancakes
Waffles
Grits
Bread
Dates
Corn
White Rice
Cornflakes
Rice Cakes
Jelly Beans
Puffed Wheat
Graham Crackers Udon Noodles
One limitation of the Glycemic Index is that it does not
consider the amount of carbohydrates a food has a
typical serving. Charts listing the glycemic index of
foods frequently standardize the amount of carbohydrates one obtains from each item (typically 50 grams).
It takes a lot of some foods to get 50 grams of carbohydrates while for other foods have a large amount of
carbohydrates in a small serving. This means that foods
that are unlikely to provoke a large insulin response
given the amount that is typically eaten, such as watermelon, have a high glycemic index. To provide fair
comparisons among foods, many charts also provide
the glycemic load of a food, which is the glycemic index
multiplied by the amount of carbohydrates in a usual
serving. One of the best web sites to compare the glycemic index and glycemic load among food items is
www.glycemicindex.com.
ing the day.25,26 Lipid concentration also seems to follow
a circadian rhythm, with meals eaten at night leading
to higher serum triglyceride levels and less concentrated
cholesterol lipoproteins when compared with daytime
meals.27
Shift Work and Sleep
Another likely reason shift work and interrupted sleep
may be related to obesity in the fire service is the food
intake that occurs before or after nighttime calls. As
several participants in the Heart Healthy Heroes study
discussed, there is often an abundance of high-carbohydrate, high-sugar foods at the fire station. Many firefighters discussed habits of snacking after calls during
the night and excess intake that would not occur if they
had not been awake at odd hours.
Emergency calls are not confined to the normal working hours of 9am to 5pm. Firefighters have to be ready
24 hours a day to respond to an alarm. This also means
responding to calls in the middle of the night and interrupted sleep. Career firefighters have set duty days,
while volunteers may be on call at any time and may
experience more frequent interrupted sleep.
Shift work and interrupted sleep can be challenging for
a number of reasons, including putting people at greater
risk for obesity. For instance, researchers in Australia
looked at a sample of nurses and midwives and found
that, even after controlling for other variables, shift
workers were 15 percent more likely to be overweight
or obese then their peers who only worked days.22 Studies in the U.S. have also found that people who sleep
less than seven hours each night have a higher likelihood of becoming obese than those who sleep seven or
more hours.23
The exact mechanisms that link sleep disturbance and
obesity are not completely understood, but several
pathways have been suggested including circadian
disturbances that result in metabolic disruption.24 The
circadian rhythm is the physiological cycle the body and
hormones go through in a 24-hour period. Disruption
to the cycle by being awake and introducing light when
the body expects to be asleep and in the dark can cause
interruption to the typical cycle. As an example, glucose
tolerance has a naturally decreasing cycle across the
course of a day, which means that foods consumed at
night are processed differently than the same meal dur-
28
Another hormone that seems particularly important in
the link between sleep and obesity is ghrelin. Ghrelin is
produced in the stomach and is a circulating hormone
that, along with leptin, signals hunger. Ghrelin increases
before meals to let your body know you are hungry and
decreases after meals to let your body know you are
full. Interruptions in the circadian rhythms of ghrelin
mean that the body signals that you are hungry even
when you are not. Studies have found that, if sleep is
interrupted, hormonal patterns are altered and people
feel more hungry.28, 29
Physical Activity
We all know that exercise is important for good health.
There is scientific evidence that exercise/physical activity
also helps with weight maintenance or prevention of
weight gain, but many people believe that if we exercise
enough, then diet does not matter as much.30-32 This is a
sentiment that has been repeated by a large number of
firefighters from all over the country. For example, one
firefighter in the Heart Healthy Heroes study stated:
“I think everybody kind of thinks, well, I can eat this
way here at work and eat healthy at home and work
out also and it curbs a lot of that bad.”
Another notion that has been discussed broadly in the
popular media and scientific circles is that the current
epidemic of obesity can be largely attributed to the
gradual decline in physical activity over the last several
decades. The following will review the evidence for
these ideas, starting with the belief that physical activity levels have declined over the last several decades,
and includes a review of the current rates of different
levels of physical activity. The section will conclude
by answering the question about whether exercise can
counteract a bad diet.
How Much Does Activity and Exercise Affect
Weight and Obesity?
Most scientists and public health experts agree that
physical activity and exercise are important for overall
health and that most Americans are not active enough.
The Centers for Disease Control and Prevention conducts an annual telephone survey of randomly selected
Americans and found that that nearly one-quarter of
adults were mostly inactive in 2004.33 However, they
also reported that since 1990 (when they started collecting physical activity information consistently) the
percentage of Americans meeting current public health
activity recommendations – which says all Americans
should engage in at least 150 minutes per week of
moderate-intensity physical activity – has been gradually increasing. Less than 25 percent of adult Americans
engaged in the recommended levels in 1990, but this
figure increased to over 26 percent by 2000, more than
40 percent by 2005, and nearly 51 percent by 2009.34,35-37
Despite these improvements, almost 50 percent of
Americans are either irregularly active or not active
at all.
Activity levels related to work and transportation also
appear to have declined over the last several decades.
A study that examined trends in occupationally-related
physical activity found that only 20 percent of jobs
now require at least moderate-intensity activity where
it was closer to 50 percent in the 1960s.38 The net result
was estimated to be a 124 and 140 calorie reduction in
energy output for women and men, respectively. This
change reflects the shift away from jobs in manufacturing or agriculture and towards those that are mostly
sedentary, i.e., sitting at a desk all day. Taken together,
this has led some scientists to conclude that there has
been an overall trend towards less physical activity
over time and that this may help to explain the obesity
epidemic in the United States.39
In contrast, other scientists using more precise methods of measuring physical activity energy expenditure
have found that activity levels have not really changed
since the 1980s (when these methods became widely
available for human activity studies). For example,
Westerterp and Speakman pulled together data from
a number of studies that used a method called Doubly
Labeled Water (DLW) to measure energy output.40 Put
simply, hydrogen or oxygen ions in water are replaced
29
with non-radioactive tracing ions. Energy expenditure
is estimated by measuring the rate at which these tracer
ions move through the body and are expelled through
urine and expiration (CO2). Westerterp and Speakman
found that from 1988 to 2006, physical activity energy
expenditure slightly increased in both the European and
North American samples. In that same time period, they
reported that obesity rates increased from 5 percent to
10 percent in the same European region and from 8
percent to 22 percent in North America.41 It has been
suggested that data from energy expenditure studies
better reflect actual trends in energy output over time.
Another interesting study using DLW evaluated activityrelated energy expenditure, physical activity level, and
changes in BMI among 40 healthy, non-obese adults
who were followed for an average of 11 years (the
study began with an average age of 27 years).41 There
were several interesting findings: 1) participants who
had high baseline physical activity levels gained more
fat at the follow-up than those with lower baseline
activity levels; and 2) fat mass changes occurred even
among participants who had not changed their physical activity levels between baseline and follow-up to the
tune of about ½ pound per year, which was associated
with aging. The authors concluded that when people
change from a physically active lifestyle to a less active
one over time, they do not appear to also reduce their
food intake, even though they need less energy.41 These
examples are not all inclusive; there are several other
studies examining energy expenditure that have produced very similar results.42
The Problem of “Compensation”
Why does it appear that physical activity may not play
as big of a role in weight loss or the current obesity
epidemic? A study by researchers at the Pennington
Biomedical Research Center in Baton Rouge, LA,
provided some insight.43 Their study compared people
who did not exercise with those who exercised for increasing amounts of time each week (72, 136, and 194
minutes per week with a personal trainer, respectively).
At the end of the six month study the data suggested
that there were no statistically significant differences
between the groups with regard to actual weight loss;
in other words, all groups lost weight (even the nonexercise group) and the differences between the groups
were very small. Specifically, the non-exercise group lost
about two pounds, while the group exercising the most
(194 minutes per week) lost a little more than three
pounds.
So, what happened here? Why were there minimal differences between the participants in the exercise groups
and those in the non-exercise group? Why did the
participants who exercised the most actually lose less
weight than those in the 136 minutes per week group
(they lost about four and a half pounds)? The researchers found that a high proportion of participants who
exercised compensated for their exercise-related caloric
output by increasing the caloric intake or decreasing
their expenditure in other ways, perhaps by eating more
because the extra activity increased their appetite, rewarding themselves with food for exercising, or engaging in less household or other physical activity.43
It should be noted that most experts do not promote
exercise or physical activity alone as a primary method
for weight loss.30-32 Eric Ravussin, an internationally
renowned obesity researcher at the Pennington Biomedical Research Center, was quoted in a 2010 New
York Times article as saying: “In general, exercise by
itself is pretty useless for weight loss.”44 The amount of
recommended activity related to improving health (i.e.,
at least 150 minutes of moderate-intensity activity) has
generally not been associated with substantial or clinically important weight loss that is comparable to what
would be considered successful as an obesity intervention. Additionally, the energy expenditure needed to
produce weight loss is very high and difficult for most
people to maintain for any length of time.31 Physical
activity levels between 150-250 minutes per week produces modest weight loss (4-7 pounds) and more than
250 minutes per week is needed to produce clinically
significant weight loss (11-16 pounds).31-32 This means
that if you worked out five days per week, you would
need to exercise between 50-80 minutes per session to
achieve any meaningful weight loss.31,32
Exercise Does Not Increase Metabolism as Much as
You Think
The current exercise guidelines to promote health from
the American College of Sports Medicine and the
American Heart Association34 (and the 2008 Physical
Activity Guidelines for American; see www.health.gov/
paguidelines) recommend at least 150 minutes per week
of moderate-intensity aerobic activity or between 60-75
minutes per week of vigorous aerobic activity, or some
combination of both. The guidelines also call for an additional two days or more of resistance/strength training
completing 8-10 exercises.34,45 Following these requirements will likely result in a moderate increase in muscle
mass and perhaps a small weight loss.30-32 However, it
should not be assumed that greater muscle mass will
30
produce a substantially higher resting metabolic rate
and protection from weight gain in the absence of a
good diet. The metabolic rate for muscle at rest is about
six calories per pound, while the rate for fat is even
lower at two calories per pound.46,47 Thus, if five pounds
of fat was replaced with the same amount of muscle, the
resting metabolic rate will be boosted by only about 20
calories per day - the equivalent of eating about onesixth of a Birthday Cake Mini Doughnut at Starbucks.
As another example, consider how much exercise would
be needed to compensate for eating a typical firehouse
meal. Consider the recipes provided at
www.firehousechef.com, a forum where firefighters can
exchange recipes. The recipes list serving sizes separately
for firefighters (e.g. a potato soup recipe states “feeds
6-8 people or 4-6 firefighters”). Many of the recipes on
the Firehouse Chef site have very high calorie counts
and often are very high in processed carbohydrates,
which rapidly raise insulin levels and are full of fat.
Crews reported they would normally eat potato soup
from the aforementioned recipe with biscuits and a dessert. Just one serving of soup with two biscuits, a piece
of cake, and a soda would result in consuming 1,699
calories in one meal per firefighter. It would require a
170 pound firefighter to engage in some form of vigorous exercise (e.g., running, stair climbing, full-court
basketball, swimming, rowing) for 90-120+ minutes to
offset the caloric load of this one meal, depending on
the activity.48
Additionally, fast foods such as pizza, burgers, etc. are
also considered staples in many firehouses. A slice of
hand-tossed pepperoni pizza from Pizza Hut has 230
calories (see www.pizzahut.com/Files/PDF/PH_
WSNationalBrochure4.13.10.pdf). A serving of three to
four slices, not unrealistic for a firefighter, has between
690-920 calories. A person weighing 180 pounds would
need to run for between 33-44 minutes at a rate of 10
miles per hour (about a six-minute mile pace) to “burn
off” that meal, while a person weighing 130 pounds
would have to run at the same pace for 45-61 minutes.
Weight influences how many calories are burned. Heavier people use more calories to support their greater
mass; therefore, lighter people must exercise longer to
expend the same amount of calories.
Diet is Important!
Exercise alone cannot overcome a poor diet. There is
very strong evidence that what we eat has greater influence over weight and body composition than exercise
alone. Combining exercise with a healthy diet is the
best way to combat obesity.” And then add a paragraph
break so the next paragraph begins with “A study that
examined changes in the food energy supply and the
weight of Americans between the 1970s and 2000s
found that adult caloric intake had increased by nearly
500 calories per day – 353 calories per day for children.49 The findings were very consistent with actual
measured weight gains among Americans participating
in a national health study during the same time period.
Large lifestyle changes over time, participating food
intake, can also explain American increases in obesity.50
In the early 1970s, women who began participation in
a national study in the 20-29 age group had an average
BMI of 23. By the time they were in the 50-59 age group,
during 1999-2002, the average BMI had increased to
29. This change represents a 35 pound weight gain over
a period of 28 years and could be accounted for by an
average increase of 370 calories per day.
Finally, one might wonder if the increase in total caloric
intake occurred because of increased intake of all foods
or just a particular type or category of food. That issue
was addressed by a group of government scientists at
the National Center for Health Statistics. Their findings were recently published in the CDC’s Morbidity
and Mortality Weekly Report.51 They analyzed nutrition data gathered from 1971-2000 from a nationallyrepresentative sample of thousands of adults aged 20-74
and found that total caloric intake increased an average
168 calories for men and 335 calories for women. More
importantly though, they also examined which macronutrients accounted for this increase in caloric consumption and found statistically significant increases in
the mean percent of calories from carbohydrates; from
42.4 percent to 49 percent for men and 45.4 percent to
51.6 percent for women, while the percent of calories
from fat and saturated fat decreased for both genders.
References
31
1
Cutler DM, Glaeser EL, Shapiro JM. Why have Americans become more obese? Journal of Economic Perspectives. 2003;17:93-118.
2
This study was funded by an early career development award from the American Heart Association’s National Center to Dr. Jahnke. Award #0830390N
3
Jahnke SA, Poston WSC, Jitnarin N, Haddock CK. Health concerns of the US Fire Service: Perspectives from the firehouse. American Journal of Health Promotion. In press.
4
The Morbidity and Mortality Weekly Report (MMWR) is free from the Centers for Disease Control and Prevention at their website (www.cdc.gov). See MMWR, February 6, 2004, volume 53, pages 80-82: “Trends in intake of energy and
macronutrients – United States, 1971 – 2000.
5
Two excellent articles that discuss the changes in our diets because of the introduction of modern agriculture and animal husbandry and the resultant negative impact on our health are: Cordain, L., et al (2005). Origins and evolution of the Western diet: health implications for the 21st century. American Journal of Clinical Nutrition, 81, 341-354 and O’Keefe, et al. (2006). Coronary artery disease prognosis and c-reactive protein levels improve in proportion to percent lowering of
low-density lipoprotein. The American Journal of Cardiology (www.AJConline.org). For instance, Cordain and colleagues conclude that “The evolutionary collision of our ancient genome with the nutritional qualities of recently introduced foods may underlie many of the chronic diseases of Western civilization.”
6
See Zelman, K. (2011). The great fat debate: a closer look at the controversy – questioning the validity of age-old dietary guidance. Journal of the American Dietary Association, 111, 655-658.
7
We highly recommend that you read this book. Taubes book focuses on two basic tenets of health promotion in the past several decades: (1) that dietary fat and especially saturated fat causes health disease and (2) that obesity is a problem of the will caused by caloric excel and/or under activity. He argues that neither of these tenets are true and that interventions based on them underlie the obesity epidemic. Taubes, G. (2007). Good calories, bad calories: fats, carbs, and the
controversial science of diet and health. New York, NY: Anchor Books.
8
For a highly entertaining video about the politics of nutrition and diet see the move Fat Head (www.fathead-movie.com/).
Be sure to see the “No-Bologna Facts” on the movie website. Jared Diamond http://anthropology.lbcc.edu/handoutsdocs/
mistake.pdf
9
For example, the Framingham Heart Study found an inverse association between dietary fat intake and stroke in men. That is, the more fat, including saturated fat, the participants consumed the lower their risk of ischemic stroke. Gillman, M.W., Cupples, L.A., Millen, B.E>, Ellison, R.C., & Wolf, P.A. (1997). Inverse association of dietary fat with development of Chapter 3 Why Is There An Epidemic of Obesity in the Fire Service?
ischemic stroke in men. Journal of the American Medical Association, 278, 2145-2150. For an interesting report of how
resistant administrators of the Framingham Heart Study were to publish data showing no link between fat intake and heart disease see Good Calories, Bad Calories, pp. 27-28.
10
In fact, the low-fat diet group had slightly higher mortality than the control group. The intervention group also included treatment for hypertension and smoking cessation counseling. See: Multiple Risk Factor Intervention Trial Research Group (1982). Multiple risk factor intervention trial. Risk factor changes and mortality results. Journal of the American Medical Association, 248, 1465-1477.
11
Howard, B.V., et al., (2006). Low-fat dietary pattern and risk of cardiovascular disease: The women’s health imitative randomized controlled dietary modification trial. Journal of the American Medical Association, 295, 655-666. It is an
interesting exercise to examine how research explains the lack of association between fat intake and health which has been demonstrated in a large number of influential studies. This has been lampooned in many books and websites, including Tom Naughton at: www.fathead-movie.com/index.php/2010/01/21 /from-a-sows-ear/. For a more scholarly critique of
attempts to explain-away the lack of relationship between dietary fat and obesity, see: Willett, W.C. (1998). Dietary fat and obesity: an unconvincing relation. American Journal of Clinical Nutrition, 68, 1149-1150.
12
For reviews of the effectiveness of traditional dietary approaches see: Jeffery, R.W., Drewnowski, A., Epstein, L.H., Stunkard,
A.J., Wilson, G.T., Wing, R.R., Hill, D.R. (2000). Long-term maintenance of weight loss: current status. Health Psychology, 19, 5-16. Mann, T., Tomilyama, A.J., Westline, E., Lew, A.M., Samuels, B., Chatman, J. (2007). Medicare’s search for effective obesity treatments: diets are not the answer. American Psychologist, 62, 220-233. Stice, E., Shaw, H., Marti, N. (2006). A meta-analytic review of obesity prevention programs for children and adolescents: the skinny on interventions that work. Psychological Bulletin, 132, 667-691. As Mann and colleagues state in their review, “there is little support for the notion that diets lead to lasting weight loss or health benefits.” They note that as a result of calorie-restricting diets, about two-thirds of dieters actually regain more weight than they lost on their diets after treatment.
13 Jared Diamond, “The Worst Mistake in the History of the Human Race,” Discover Magazine, May 1987, pp. 64-66.
14 For instance, see Gadsby, P. (2004). The Inuit paradox: how can people who gorge on fat and rarely see a vegetable be healthier than we are? URL: http://discovermagazine.com/2004/oct/inuit- paradox/article_print.
15
Siri-Tarino, P.W., Sun, Q., Hu, F.B., Krauss, R.M. (2010). Meta-analysis of prospective cohort studies evaluating the
association of saturated fat with cardiovascular disease. American Journal of Clinical Nutrition, 91, 535-546. Siri-Tarino, P.W., Sun, Q., Hu, F.B., Krauss, R.M. (2010). Saturated fat, carbohydrates, and cardiovascular disease. American Journal of Clinical Nutrition, 91, 502-509. See articles about saturated fats on the Weston A. Price Foundation website at:
www.westonaprice.org/. Note that this foundation has received criticism from Vegan and Vegetarian groups such as:
www.vegsource.com/articles2/fuhrman_facts_fiction.htm
16
For instance, see Willett, W. (2003). Concepts and controversies on diet: Stop recommending low-fat diets! The Permanente Journal, 7, 24-33. For comparisons of low fat to low carbohydrate diets, see: Gardner, C.D., Kiazand, A., Alhassan, S., Kim, S., Stafford, R.S., Balise, R.R., Kraemer, H.C., & King, A.C. (2007) Comparison of the Atkins, Zone, Ornish, and LEARN Diets for Change in Weight and Related Risk Factors Among Overweight Premenopausal Women: The A TO Z Weight Loss Study: A Randomized Trial. Journal of the American Medical Association, 297, 969-977. Yancy, W.S., Westman, E.C., McDuffie, J.R., Grambow, S.C., Jeffreys, A.S., Bolton, J., Chalecki, A., Oddone, E.Z. (2010). A randomized trial of a low-
carbohydrate diet vs orlistat plus a low-fat diet for weight loss. Archives of Internal Medicine, 170, 136-145. See also
Hession, M., Rolland, C., Kulkarni, U., Wise, A., Broom, J. (2008). Systematic review of randomized controlled trials of low-carbohydrate vs. low fat/low-calorie diets in the management of obesity and its comorbidities. Obesity Reviews, 10, 36-50. The authors of this review note that “There was a higher attrition rate in the low-fat compared with the lowcarbohydrate groups suggesting a patient preference for a low-carbohydrate/high-protein approach as opposed to the Public Health preference of a low-fat/high-carbohydrate diet.” Our impression in over 20 years of clinical work and research in obesity is that most patients cannot tolerate a low fat diet along with calorie restriction very long, and these types of diets often results in low mood and irritability. In contrast, those on low-carbohydrate diets such as the Paleo Diet or Zone Diet report to us that their energy level and mood increase.
17 See an interesting commentary by Gary Taubes on how the deck is often stacked against low-carbohydrate diets in
comparative studies at: www.garytaubes.com/2010/12/calories-fat-or-carbohydrates/
18 For example, see Volek, J.S., Sharman, M.J., Gomez, A.L., Judelson, D.A., Rubin, M.R. (2004) Comparison of energy
restricted very low-carbohydrate and low-fat diets on weight loss and body composition in overweight men and women. Nutrition & Metabolism, 1:13. URL: www.nutritionandmetabolism.com/content/1/1/13.
19
32
There are many references in the medical literature which point to the health benefits of low-carbohydrate diets. Note that many of these diets are rich in vegetables and some fruits but typically avoid grains, starchy vegetables, processed
carbohydrates, and sugar. Volek, J.S., Phinney, S.D., Forsythe, C.E., Quann, E.E., Wood, R.J., Puglisi, M.J., Kraemer, W.J., Bibus, D.M., Fernandez, M.L., Feinman, R.D. (2008). Carbohydrate restriction has a more favorable impact on the
metabolic syndrome than a low fat diet. Lipids, 44, 297-309. Volek, J.S., Feinman, R.D. (2005). Carbohydrate restriction improves the features of metabolic syndrome. Metabolic syndrome may be defined by the response to carbohydrate
restriction. Nutrition & Metabolism, 2: 31. Elhayany, A., Lustman, A., Abel, R., Attail-Singer, J., Vinker, S. (2010). A low
carbohydrate Mediterranean diet improves cardiovascular risk factors and diabetes among overweight patients with type 2 diabetes mellitus: a 1-year prospective randomized intervention study. Diabetes, Obesity, and Metabolism, 12: 204-209.
20 Volek, J.S., Feinman, R.D. (2005). Carbohydrate restriction improves the features of metabolic syndrome. Metabolic
syndrome may be defined by the response to carbohydrate restriction. Nutrition & Metabolism, 2: 31.
21
See an online Slate article by Melinda Wenner Moyer called “End the war on fat: It could be making us sicker” posted March 25, 2010 for an interesting discussion of the role the glycemic index plays in our health (www.slate.com/id/2248754/). The writer also reviews evidence that saturated fats are, at worse, neutral in their impact on our health while polyunsaturated fats are likely good for our hearts.
22 Zhao I, Bogossian F, Song S, Turner C. The association between shift work and unhealthy weight: A cross-sectional analysis from the Nurses and Midwives’ e-cohort Study. J Occup Environ Med. 2011; 53:153-158.
23 Gangwisch JE, Malaspina D, Boden-Albala B, Heymsfield SB. Inadequate sleep as a risk factor for obesity: Analyses of the NHANES I. Sleep. 2005; 28: 1289-1296.
24 Knutsson A, Boggild H. Shiftwork, risk factors and cardiovascular disease: Review of disease mechanisms. Rev Environ Health. 2000:15;359-372.
25 Lund J, Arendt J, Hampton SM, English J, Morgan LM. Postprandial hormone and metabolic responses among shift workers in Antarctica. J Endocrinal 2001; 171: 557-564.
26 Holmback U, Forslund A, Forslund J, Hambraeus L, Lennernas M, Lowden A, et al. Metabolic responses to nocturnal eating in men are affected by sources of dietary energy. J Nutr 2002; 132: 1892-1899.
27 Romon M, LeFur C, Lebel P, Edme J, Fruchart J, Dallongeville J. Circadian variation of postprandial lipemia. Am J Clin Nutr. 1997; 65: 934-940.
28 Copinischi G. Metabolic and endocrine effects of sleep deprivation. Essential Psychopharmacology. 2005; 6:341-347.
29 Speigel K, Tasali E, Penev P, et al. Brief communication: Sleep curtailment in healthy young men is associated with decreased leptin levels, elevated ghrelin levels and increased hunger and appetite. Ann Intern Med. 2004; 141: 846-850.
30 Hill JO, Wyatt HR. Role of physical activity in preventing and treating obesity. Journal of Applied Physiology 2005;99:
765-770.
31 Catenacci VA, Wyatt HR. The role of phsycial activity in producing and maintaining weight loss. Nature Clinical Practice Endocrinology & Metabolism 2007;3:518-529/
32 Donnelly JE, Blair SN, Jakicic JM, Manore MM, Rankin JW, Smith BK. Appropriate physical activity intervention for weight loss and prevention of weight regain for adults. Medicine & Science in Sports & Exercise 2009;41(2):459-71.
33 Kruger J, Ham SA, Kohl HW. Trends in leisure-time physical inactivity by age, sex, and race/ethnicity – United States, 1994--
2004. MMWR 2005;54:991-994.
34 Haskell WL, Lee IM, Pate RR, Powell KE, Blair SN, Franklin BA, Macera CA Health GW, Thompson PD, Bauman A.
Physical activity and public health: Updated recommendation for adults form the American College of Sports Medicine and the American Heart Association. Medicine & Science in Sports & Exercise 2007;116:1081-1093.
35 Kruger J, Kohl HW. Prevalence of regular physical activity among adults – United States, 2001 and 2005. MMWR 2007;56:1209-1212.
36 Hootman JM, Macera CA, Ham SA, Helmick CG, Sniezek JE. Physical activity levels among the general US adult population and in adults with and without arthritis. Arthritis & Rheumatism (Arthritis Care & Research) 2003;49:129-135.
37 CDC. Prevalence and trends data. Physical activity – 2009, All States. Adults with 30+ minutes of moderate physical activity five or more days per week, or vigorous physical activity for 20+ minutes three or more days per week. Accessed at
http://apps.ncce.cdc.gov/bfrss/list_PF.asp on 2 June 2001.
38 Church TS, Thomas DM, Tudor-Locke C, Katzmarzyk PT, Earnest CP, Rodarte RQ, Martin CK, Blair SN, Bouchard C. Trends over 5 decades in U.S. occupation-related physical activity and their association with obesity. PLos ONE 2001;6:e19657.
39 Brownson RC, Boehmer TK, Luke DA. Declining rates of physical activity in the United States: What are the contributors? Annual Review of Public Health 2005;26:421-443.
33
40 Westerterp KR, Speakman JR. Physical activity energy expenditure has not declined since the 1980s and matches energy expenditures of wild mammals. International Journal of Obesity 2008; 32(8):1256-1263.
41 Westerterp KR, Plasqui G. Physically active lifestyle does not decrease the risk of fattening. PLos ONE 2009;4:e4745.
42 Ebersole KE, Dugas LR, Durazo-Arvizu RA, Adeyemo AA, Tayo BO, Omotade OO, Brieger WR, Schoeller DA, Cooper RS, Luke AH. Energy expenditure and adiposity in Nigerian and African-American women. Obesity 2008;16:2148-2154.
43 ChurchTS, Martin CK, Thompson AM, Earnest CP, Milkus CR, Blair SN. Changes in weight, waist circumference, and compensatory response with different doses of exercise among sedentary, overweight postmenopausal women. PLos ONE 2009;4:e4515.
44 Reynolds G. Weighing the evidence on exercise. New York Times, April 16, 2010. Accessed at
www.nytimes.com/2010004/18/magazine/18exercise-t.html on 2 June 2011.
45 International Association of Fire Fighters/International Association of Fire Chiefs. The Fire Service Joint Labor Management Wellness-Fitness Initiative, 3rd Edition. Washington, DC: International Association of Fire Fighters, 2008.
46 Cloud J. Why exercise won’t make you think. TIME August 9, 2009. Accessed at
www.time.com/time/printout/0,08816,1914857,00.html on 26 May 2011.
47 Wolfe RR. The underappreciated role of muscle in health and disease. American Journal of Clinical Nutrition 2006;84:
475-482.
48 Ainsworth BE, Haskell WL, Whitt MC, Irwin ML, Swartz AM, Strath SJ, O’Brien WL, Bassett DR, Schmitz KH,
Emplaincourt PO, Jacobs DR, Leon AS. Compendium of physical activities: An update of activity codes and MET intensities. Medicine & Science in Sports & Exercise 2000; 32(9 Suppl):S498-504.
49 Swinburn B, Sacks G, Ravussin E. Increased food energy supply is more than sufficient to explain the US epidemic of obesity. American Journal of Clinical Nutrition 2009;90:1453-1456.
50 Katan MB, Ludwig DS. Extra calories cause weight gain—But how much? JAMA 2010;303:65-66.
51 Wright JD, Kennedy-Stephenson J, Wang CY, McDowell MA, Johnson CL. Trends in intake of energy and macronutrients – United States, 1971-2000. MMWR 2004;53:80-82.
34
Chapter 4
Innovative Trends in Obesity
and Fitness Research
Natural Whole Foods I CrossFit® I Fruits I Nuts and Seeds I Spices I Slow Food Movemen
Chapter 4 Innovative Trends in Obesity and Fitness Research
This chapter will review three promising trends in diet
and nutrition in the United States: the importance of
natural whole foods, the Slow Food Movement, and
ancestral eating. In addition, it will look at a significant trend in exercise among industrial athletes such as
military, police, and firefighters – high intensity training
(HIT), which focuses on functional exercises (FE) or
movements. This includes an overview of CrossFit®, a
popular FE workout in the fire service.
Natural Whole Foods
In his book Food Rules: An Eater’s Manual, nutrition
and health writer Michael Pollan lists 64 rules to follow
if you want a healthy diet.7 His simple rules include:
>Don’t eat anything your great-grandmother wouldn’t recognize as food.
>Avoid food products containing ingredients that no ordinary human would keep in the pantry.
>Avoid foods that have some form of sugar (or sweet-
ener) listed among the ingredients.
>Avoid foods that contain more than five ingredients.
>Avoid food products containing ingredients that a third-grader cannot pronounce.
>Avoid food products that make health claims.
>Avoid food products with the word “lite” or the terms “low-fat” or “nonfat” in their names.
>Avoid foods that are pretending to be something they are not (for example, margarine).
>Avoid foods you see advertised on television.
>Shop the peripheries of the supermarket and stay out of the middle.
Most of the products at a fast food restaurant or in
the middle aisles of a grocery store would not comply
with any of these rules. Take a look at a typical bag of
potato chips or a pre-prepared dinner in the frozen food
aisle. Pollan calls these types of food “edible foodlike
substances” to distinguish them from real foods (think
broccoli, shrimp, or an apple). They may be tasty, but
they have been engineered by food scientists to trick the
body into craving them and think they taste great.
For example, examine the ingredients in a Ham and
Cheese Hot Pocket®. Are you ready? Breathe in deeply
and try to read this list before taking another breath:
unbleached enriched flour (wheat flour, malted
barley flour, niacin, reduced iron, thiamin mononitrate, riboflavin, folic acid), water, ham water
added ground and formed, natural smoked flavor
36
added (cured with water, sugar, salt, sodium phosphates, natural smoke flavor, sodium erythorbate,
sodium nitrite), part skim mozzarella cheese with
modified food starch (part skim mozzarella cheese
[pasteurized milk, cultures, salt, enzymes], modified food starch, flavor, annatto), imitation cheddar cheese (water, modified food starch, casein,
soybean oil, whey, contains 2% or less of salt,
sodium aluminum phosphate, sodium phosphate,
lactic acid, sodium citrate, natural flavor, sorbic
acid [preservative], artificial color), seasoning
(whey, cheddar cheese [milk, cheese cultures, salt,
enzymes], buttermilk, enzyme modified cheddar
cheese [milk, sodium citrate, cheese culture, salt,
enzymes, potassium sorbate], salt, reduced lactose whey, coconut oil, maltodextrin, disodium
phosphate, blue cheese [milk, cheese culture, salt,
enzymes], citric acid, lactic acid, extractives of annatto and turmeric [color]), contains less than 2%
of: palm oil (with soy lecithin, artificial flavor, beta
carotene), modified food starch, seasoning (toasted
bread crumbs [wheat flour, sugar, yeast, soybean
oil, salt], cheddar cheese [milk, cheese cultures,
salt, enzymes], salt, whey, dextrose, dehydrated
onion, natural flavor, soybean oil, garlic powder,
reduced lactose whey, disodium phosphate, citric
acid, lactic acid, disodium inosinate & guanylate, spice, blue cheese [milk, cheese cultures, salt,
enzymes], extractives of paprika & annatto), sugar,
seasoning (whey, partially hydrogenated soybean
oil, maltodextrin, cheddar/blue cheese [pasteurized
milk, cheese cultures, salt, enzymes], salt, nonfat
milk, sodium caseinate, sodium citrate, natural
flavors, citric acid, extractives of annatto, paprika
and turmeric [color]), partially hydrogenated palm
kernel oil (with soy lecithin, citric acid as preservative), salt, dough conditioner (calcium sulfate,
distilled monoglycerides, salt, l-cysteine hydrochloride, garlic powder, tricalcium phosphate, enzymes,
ascorbic acid, citric acid, BHT), yeast, dried egg
yokes, lactic acid, dried whey, soy flour, dried egg
whites.8
Whew! For fun, look up some of the more interestinglooking ingredients. Learn about delectable additives
such as L-cysteine (usually derived from human hair or
duck feathers) and BHT (which also shows up in the ingredient lists for cosmetics and jet fuel). The same long
list of ingredients certainly would not be found in a
healthy serving of spinach sautéed in olive oil or a piece
of fresh, wild-caught grilled salmon.
The scientifically-engineered taste and convenience
comes with a huge price. If there is one fact in nutritional science that nearly everyone agrees on (and there
are few), it is that with a Western diet full of processed
foods including refined grains, sugar, and difficult-topronounce ingredients, diseases such as obesity, cardiovascular disease, cancer, and diabetes explode. Those
who eat traditional diets usually do not suffer from
these diseases, even when they live long lives. If all of
Pollan’s rules could be condensed down to one, it would
be: Eat real food, not processed food.
“All of our uncertainties about nutrition should not
obscure the plain fact that the chronic diseases
which now kill most of us can be traced directly
to the industrialization of our food: the rise of
highly processed foods and refined grains; the use
of chemicals to raise plants and animals in huge
monocultures; the superabundance of cheap calories
of sugar and fat produced by modern agriculture;
and the narrowing of the biological diversity of the
human diet to a tiny handful of staple crops, notably
wheat, corn, and soy.”
Michal Pollan, In Defense of Food: An Eater’s Manifesto9
Eating real meats, vegetables, fruits, nuts, and seeds,
primarily those that are raised or grown near where you
live, will dramatically improve diet and health. There is
a good reason that farmer’s markets, community-supported agriculture (CSA), and eating foods free of additives and chemicals are all the rage among the health
and fitness crowd. Staying away from those middle food
aisles can lead to better health, more energy, and will
help to achieve or maintain a healthy weight. Refer to
the chart for examples of real foods.10
Meats:
Mix these tasty, nutritious foods and spices in limitless
combinations that are sure to satisfy the taste buds.
Avoid foods that required a factory to produce, including cooking oils (e.g., canola, corn, soybean, safflower)
that are hydrogenated or partially hydrogenated; trans
fats; sugary beverages like energy drinks; sports drinks;
high-fructose corn syrup; sweetened teas and sodas;
bread products like bagels, biscuits, pancakes, croissants, crackers, and donuts; white rice; fast foods;
deeply fried foods, particularly those that are coated in
white flour before frying; foods that come in a box or
wrapper such as cereals; granola bars; pretzels; chips;
rice cakes; and sugary desserts such as cookies, cake,
pie, ice cream, etc. All of these foods are recent additions to the human diet and have contributed to the
epidemic of obesity.
37
Real Foods
Fruits
Apples, pomegranates, watermelon, pineapple,
bananas, cherries, melons, berries, pears, papayas
Don’t overdo fruit given their high sugar content,
and favor berries. Locally grown and organic fruit
are best
Nuts and Seeds
Almonds, walnuts, pistachios, Brazil nuts, and
macadamia nuts (note: peanuts are not nuts, they
are legumes)
Also try almond butter and almond flour for a tasty
alternative to less healthy foods. These are highly
nutritious and filling
Oils
Coconut oil, butter (much healthier than margarine
and much tastier!), olive oil
Try first press olive oils…they are delicious!
Spices
Parsley, sage, rosemary, thyme, curry, paprika,
cumin, cinnamon, garlic, ginger, nutmeg
Learn about the many health benefits and taste
pleasures of spices. They make food delicious while
promoting health!
Dairy
Use dairy in moderation or not at all if you are
lactose intolerant
Focus on organic versions of milk and cheese.
Beware that many yogurts, even those advertised
as healthy, contain high-fructose corn syrup
There are many substitutes to these foods that can be
found in health-focused cookbooks or on the Internet.
For instance, spaghetti squash provides a delicious
and healthy substitute for processed flour noodles,
and there are recipes based on cauliflower which are
great substitutes for traditional, high-glycemic mashed
potatoes. Desserts such as ice cream used to be considered “treats” and not a staple of one’s diet. If you have
ice cream, eat the best quality ice cream you can find,
have it only on special occasions, be careful about the
portion size, and savor every bite. You might find that
you enjoy it even more when focusing on high-quality
versions during special occasions.
The Slow Food Movement
An interesting segment of the increasing focus on real
foods is the Slow Food Movement, which was founded
in 1986 by Carlo Petrini.11 The Slow Food Movement
encourages the preservation of traditional and regional
cuisine, an interest in food including where it comes
from and how it tastes, and the farming of plants, seeds,
and livestock characteristic of the local ecosystem. This
movement hopes to swing the pendulum away from
“fast food” and our decreased emphasis on traditional
food preparation.
The Slow Food manifesto states that we are missing out
on one of the most pleasurable, healthy parts of our life
by abandoning traditional eating and real food. Most
people, particularly in the United States, give very little
thought to what they eat, where their food comes from,
or what impact it will have on their health. Given the
large role food plays in our health and happiness, the
Slow Food Movement says that it is time to refocus on
food. Rediscovering the tastes of real foods cooked in
traditional ways can reignite taste buds that have been
hijacked by fast foods, highly-processed foods, and
foods loaded with sugar and chemicals.
Doing anything with the word “slow” in it may seem
like a tricky task for members of a profession where
emergencies and time pressures often are the norm.
However, refocusing on real, traditional food is possible
in the firehouse and there are plenty of firefighters from
busy departments that are doing it.
Ancestral Eating
38
When biologists study the natural world, one of the
most important lenses they use in their work is evolution acting through natural selection. In the language of
science, a genetic trait that is “concordant” with environmental pressures tends to be good for an organism
and his or her offspring while “discordant” traits typically spell trouble. When there is a permanent change
in environmental conditions, organisms may experience
a period of evolutionary discordance that can lead to
disease and death. Dr. Loren Cordain, a professor at
the Colorado State University and prominent nutrition
scientist, argues that this is exactly what has happened
over the last few hundred years to humans.12
Our hunter-gatherer (HG) ancestors suffered few of
the diseases that currently plague us. Common medical
problems such as cavities, degenerative diseases, cancer,
diabetes, cardiovascular disease, and even acne were
virtually nonexistent. They had surprisingly low infant
mortality rates and despite being more susceptible to accidents, predators, and infectious disease and no access
to modern medicine, between 10 and 20 percent lived
into their sixties. They were physically fit even late into
life and often had bodies that would rival an Olympic
athlete. Even the elderly HGs were lean and muscled
and were very fit despite diets which were typically
loaded with animal foods and high in dietary fat. These
findings have been confirmed in existing groups of
hunter-gatherers (e.g., !Kung, Lufas, Eskimos, Yanomamo Indians) which have been extensively studied by
anthropologists.13
Cordain and colleagues report that the following foods
were rarely, if ever, eaten by our HG ancestors: dairy
products, cereal grains, refined sugars, refined vegetable
oils, salt, and fatty factory-raised meats.12 Adopting a
diet consistent with evolutionary history is an exciting
trend in health and fitness. A large number of fitness
experts, professional athletes, and firefighters have reported dramatic improvements in fitness by adopting a
similar diet to the one consumed by our HG ancestors.
It is not surprising that a diet focused on organic meats,
vegetables, fruits, nuts, and seeds (Paleolithic foods)
promote health while diets that are high in processed
carbohydrates and sugar (Neolithic foods) result in
obesity, diabetes, cancer, and cardiovascular disease.
Diets based on eliminating Neolithic foods have even
been recommended as effective treatments for problems that frequently plague children (and some adults)
such as acne, autism, and attention deficit hyperactivity
disorder.14
Firefighters’ Fitness Needs
There is no doubt that firefighting is physically demanding and strenuous. Firefighters are required to lift heavy
objects, drag hoses, breach doors, use heavy extrication
equipment for rescues, lift and transport patients with
emergency medical needs, etc. Often, these activities
are performed in less than optimal or even extreme
conditions while wearing up to 50 pounds of protective equipment – increasing the risk of exertion, heat
stress, and dehydration. There is wide agreement that
firefighters must maintain high levels of fitness due to:
1) strenuous job requirements, 2) cardiovascular disease
(CVD), which is the leading cause of line-of-duty death,
and 3) high injury rates that cost an estimated $2.7$7.8 billion dollars per year.16,17,18,19
Despite this reality, a large percentage of firefighters are
overweight or obese.20 Even more, many firefighters are
not demonstrating high levels of fitness.21,23,26 This is
probably at least partly related to the fact that less than
30 percent of fire departments have any structured fitness monitoring or improvement programs available to
their firefighters.21 Solid research consistently finds that
physical fitness is related to job-relevant and simulated
firefighting tasks, with fitter firefighters demonstrating better performance.28-30 For example, one study
found that firefighters who were more fit were able to
complete the tasks (e.g., hose and ladder carry, donning SCBA, climbing three flights of stairs, rescue and
body drag, etc.) much faster than those who were less
fit.28 Research has also found that fitter and stronger
firefighters are much better able to complete job performance tasks such as hose pulls, stair climbs carrying
equipment, and victim drags.30
Physical fitness is also related to a number of other
important health parameters relevant to firefighters. For
example, studies in related occupational groups such
as the military find that those who are very fit are less
likely to be injured and have lower stress symptoms
related to their job.31-33 The medical literature has demonstrated that a high level of fitness reduces the risk for
premature death and disease (e.g., CHD, stroke, colon
cancer) and can even lower some risk associated with
being overweight.34,42
Current public health recommendations suggest that all
Americans should get at least 150 minutes per week of
moderate-intensity aerobic activity or 75 minutes per
week of vigorous aerobic activity, or some combination
of both, along with an additional two days or more
of resistance/strength training that involve all major
muscle groups to promote health. Additional health
benefits can be achieved by increasing to 5 hours (300
minutes) a week of moderate-intensity aerobic physical
activity, or 2 hours and 30 minutes a week of vigorousintensity physical activity.43 It is not clear whether the
basic activity recommendations for all adult Americans
would be sufficient for meeting the needs of firefighters
beyond just promoting health. It can be argued that,
firefighters, as well as military service members and
other first-responder groups, are more appropriately
viewed as “Industrial Athletes” for whom high levels of
fitness should be the norm.43-45 For example, firefighters
often have to perform at peak levels during activities
that may involve lifting heavy objects or people, climbing ladders or flights of stairs while wearing 50 pounds
or more of protective equipment, or engaging in high
39
levels of anaerobic activity requiring substantial muscular endurance, all while under conditions of heat stress
and dehydration and with little or no “warm-up time”
before maximal efforts.44-46
Given the physical demands of firefighting, it has been
suggested that the minimum physical activity recommendations suggested for promoting general health
would not be rigorous or job-specific enough to accomplish the fitness requirements necessary to successfully
engage in many or most of the strenuous tasks involved
in firefighting and rescue activities.44,46 Several experts
in fire service fitness suggest that firefighters need to
develop and maintain high levels of general physical
preparedness, muscular strength, muscular endurance,
cardiovascular endurance, anaerobic endurance, and
job-specific strength and endurance capacities (e.g.,
specialty fitness skills related to fire suppression and
rescue activities) in order to safely and capably perform
the variety of tasks involved in the profession.30,44,47
Others have suggested that at a minimum, a firefighter
should be able to engage in activity at the intensity level
approximately equivalent to running at 7 mph on a flat
hard surface.21,47
Only two studies that attempted to improve fitness in
firefighters using traditional exercise prescriptions were
identified for this report. Both primarily focused on
improving a variety of health behaviors as well as aerobic endurance and subsequently failed to significantly
improve firefighter fitness. A study by Reid and Morgan
tested interventions designed to improve adherence
and aerobic conditioning over six months.48 Firefighters were randomly assigned to a control group or one
of two exercise groups. The exercise interventions were
based on providing general exercise principles and designing the program to fit the needs of each individual.
Primary outcomes included adherence to the exercise
program and improvements in aerobic exercise. At the
end of six months, there were no significant differences
between the two exercise groups and the control participants, who did not get any exercise programming, with
respect to maintaining an exercise program or aerobic
endurance.
More recently, Elliot and associates compared two versions of a health promotion intervention with a large
group of firefighters in their Promoting Healthy Lifestyles: Alternative Models’ Effects (PHLAME) Firefighter Study, one that provided a group-based curriculum
program and one that provided each firefighter with individualized motivational counseling.49 These conditions
were compared to a control group that was assessed in
a manner similar to the other groups, but did not receive any of the health promotion intervention components. Participants in both intervention groups received
a manual that provided information on physical activity,
nutrition, and other health issues. While participants in
both intervention groups had greater increases in the
number of sit-ups performed in one minute (1.7 for
team program, 1.4 for individual counseling, 0.8 for the
control group), there were no improvements based on
group status on outcomes such as aerobic endurance or
a measure of healthy physical activity behaviors.
Introduction to High Intensity Training and
Functional Exercise
High Intensity Training (HIT)
HIT is a method of exercising that has been demonstrated to improve athletic performance, improve endurance and strength in non-athletes, and to safely aid in
the rehabilitation of individuals with significant medical
conditions (e.g., heart failure).50-52 It has been suggested
that HIT may be an economical, time-sensitive, and
effective method for improving the fitness and health
of first responders such as firefighters, EMS professionals, law enforcement officers, and military personnel.53
Research suggests that HIT confers many of the outcomes associated with traditionally higher volume and
time-intensive aerobic and resistance training protocols
with substantially less training time and lower volumes
of work.54-55
HIT Methodology
As the name implies, a principle characteristic of any
HIT approach is that the exercise period should be
performed at a high level of effort and will often be
accomplished in shorter periods of time. In addition,
these intense and brief exercise efforts generally are
interspersed with periods of rest or lower-intensity
activity that allow for recovery so that the individual
can engage in further HIT exercises.51 For instance, one
popular HIT approach is called the “Tabata Protocol”
and involves eight repetitions of 20-second intervals
consisting of a very high-intensity activity separated by
10-second rest periods.56 Approaches to HIT utilize a
variety of exercises and methods of implementation including a mixture of both resistance and non-resistance
aerobic interval training.50 Exercises used have included,
but are not limited to, sprinting, rowing, skiing, weightlifting, cycling, etc.50,56
Effectiveness of HIT
HIT provides numerous benefits including important
40
metabolic and physiological adaptations such as improvements in cardiovascular health, lowered blood
pressure, improved body composition, and improved
glucose and insulin levels.51,55,57 Importantly, HIT does
not appear to compromise power, speed, and strength or
promote the “wear and tear” to the body that is often
experienced with sustained aerobic workouts.58
Because HIT is performed at substantially higher intensities than typical aerobic or resistance training, it can
be implemented in considerably briefer training periods.
54,56,59,61-62
It appears that HIT can accomplish many of
the outcomes associated with traditionally higher volume and time-intensive aerobic and resistance training
with substantially less training time and lower volumes
of work.54,55,56,59-62 Given the time pressures on firefighters, this is an important benefit.
Health Benefits of HIT
The medical literature on the health benefits of HIT is
impressive. Compared to moderate activity or “long and
slow” aerobic training, HIT:
>Results in greater improvements in blood pressure and the health of the heart muscle.51, 55
>Produces substantial reductions on VLDL cholesterol and triglycerides.63
>Significantly increases muscle oxidation, which can increase fat oxidation and thus lower your body
fat.54, 61-64
>Improve your VO2max - maximum capacity of an individual’s body to transport and use oxygen during
incremental exercise - as much as those long
traditional aerobic sessions with substantially shorter training times.56,61
>Unlike those long traditional aerobic sessions, HIT does not negatively impact anaerobic capacity and strength.56,66
>HIT has been shown to produce impressive improve-
ments in athletes on outcomes such as explosive movements, endurance tests, and strength.50, 67-69
>HIT has been found to be safe and effective when used with medically compromised individuals, such as those with coronary artery disease, chronic obstruc-
tive pulmonary disease, and even heart failure.51, 52, 70
Evaluations of HIT-Oriented Programs for
Firefighters
Roberts and colleagues evaluated a 16-week HIToriented program for 115 newly hired firefighter
recruits.47 The program was conducted three days per
week for one hour per session that included warmup and stretching; high intensity aerobic conditioning
including sprint intervals, strength, core, and muscle
endurance training with traditional and job-related
equipment (e.g., hoses, obstacle course, victim drag/rescue); and finished with cool-down and stretching time.
Program outcomes included changes in aerobic capacity,
muscular strength and endurance, flexibility, and body
composition. At the end of 16-weeks, recruits experienced significant improvements in aerobic capacity (a
28 percent increase in VO2max), muscular endurance,
and flexibility. It should be noted that recruits’ average
aerobic capacity at baseline (VO2max = 35.0 mL/kg/min)
was substantially below levels suggested as the minimal
necessary for fire suppression activities and that the
intervention resulted in improving the group average
to the acceptable level.21, 47 The HIT-oriented program
also resulted in reductions in body fat percentage and
increases in lean muscle mass, and all of these improvements occurred with a total training time of three hours
per week including warm-up, stretching, training, and
cool-down time.
Functional Exercise (FE)
Functional movements are defined as “natural” movements that require universal motor recruitment patterns found in everyday life. Functional movements are
typically multi-joint or compound movements and are
irreducible, i.e., the functional movement of squatting
cannot be effectively broken down into smaller parts.
Thus, while it would be difficult to develop a strong
squat by limiting oneself to doing seated leg press, leg
extensions, and calf raises, an individual with a strong
squat also will be strong when they perform leg presses,
leg extensions, and calf-raises. In addition, functional
movements are transferable to other tasks while isolated
movements are less transferable.
Olympic Lifting (OL) and Powerlifting exercises are
highly functional and mimic activities firefighters will
face in the field, albeit under more controlled circumstances. Thus, a firefighter is able to test his or her
strength and ability to perform functional movements
similar to job-related tasks in a controlled environment.
Furthermore, the literature is rich with studies that
demonstrate the health benefits of weightlifting. For
example, weightlifting has been documented to induce
muscular growth (hypertrophy), partially due to its
ability to elicit acute hormonal responses that enhance
tissue remodeling.72 Lifts that mobilize large numbers of
muscle groups, like squats, deadlifts, etc. and their vari-
41
ous training progressions are the most efficient method
for eliciting favorable muscle growth.
Weightlifting can result in improvements in aerobic
and anaerobic endurance, body composition, and bone
density. For example, Sentija, Marsic, and Dizdar evaluated the effect of a 12-week, 3x/week OL program in
moderately active men.73 After the program, participants demonstrated significant improvements in anaerobic and aerobic endurance and also experienced a small
increase in their BMI. In another study, the combination
of HIT-OL and jogging resulted in developing optimal
muscle strength and lean body mass without decrements
in aerobic capacity.74 In addition, Olympic weightlifters
demonstrate significantly greater bone mineral density
at all measured sites when compared to age-matched
controls.75
Concerns about injuries related to weightlifting and/
or physical training have been raised by members of
the fire service. However, injury rates associated with
weightlifting, particularly when individuals are provided
adequate training and supervision, are likely to be low.
Jones and colleagues examined 20-year trends (19781998) in weight training injuries that were reported by
emergency departments in U.S. hospitals to the National
Electronic Injury Surveillance System.76 While weightlifting injuries increased 35 percent over 20 years, the
U.S. population also increased about 20 percent during
the same time period. The most common causes of injuries were unsafe behavior, equipment malfunction, and
lack of supervision. While the group most likely to get
injured were adolescent/young adult males (ages 15-24),
there were also increases in injury rates among females
and older males. Taken together, the data suggests that
the increases were largely a result in U.S. population
growth and greater participation rates among groups
that typically did not engage in weightlifting in the past.
Weightlifting in general, and OL in particular, provides
a safe and highly effective form of functional exercise
for firefighters.
CrossFit®: A Useful Method of HIT and FE
Training for Firefighters
Given that many firefighters may suffer from low levels
of physical fitness, it is incumbent on leaders in the fire
service to seek out and evaluate effective methods for
promoting high levels of fitness among their personnel.21,23,26 One fitness program that has become popular
among firefighters is CrossFit®. The increasing interest
in CrossFit is entirely a grassroots phenomenon with no
known endorsement by any national fire service organization. Several fire departments have facilities supporting CrossFit workouts, and firefighters who do CrossFit
have organized national training sites on the Internet.
For example, personnel from a number of different fire
departments in the U.S. have developed their own web
sites that introduce interested personnel to CrossFit programming and prescribe “workouts of the day” (WODs)
for firefighters.77
Three recent issues of the CrossFit Journal focused on
how firefighters in a number of fire departments have
used CrossFit in an effort to increase the fitness levels of
their personnel.78-80 Police and fire service personnel in
the Kirkland, WA, and Springfield, MO, areas compete
in annual CrossFit competitions and several firefighters own CrossFit gyms. Finally, as part of three large
ongoing studies of fire departments across the United
States, the authors of this report have witnessed a large
number of firefighters who use CrossFit as their core
fitness program.
CrossFit utilizes exercise (e.g., weightlifting, plyometrics, gymnastics, etc.), progressions, and interval approaches from such a wide variety of sources, there is
no limit to the number of combinations that can be
developed for WODs that will be challenging, novel,
and promote ongoing strength and conditioning for
firefighters at no cost to individual firefighters or their
departments. In addition, the workouts often require
minimal or no equpment. Given the apparent popularity of CrossFit among firefighters and the fact that
programming is free and open-source (see www.crossfit.
com), as opposed to other HIT-oriented approaches
(e.g., P90X, Insanity, etc.), it is incumbent on fire chiefs,
training officers, Health and Wellness Advocates, and
Peer Fitness Trainers to have a basic understanding of
fitness programs to implement within the department.
Overview of CrossFit
The aim of CrossFit is to create broad, general, and inclusive fitness in the program’s participants.81 Elements
of CrossFit training include a blend of metabolic conditioning, gymnastics, and weightlifting within an environment of sport and competition. In addition, CrossFit
encourages participants to adhere to a dietary plan that
they believe maximizes performance and health, the two
most popular being the Zone and the Paleo diets.82,83
CrossFit often is referred to as the “Sport of Fitness”
because of the use of competition and group camaraderie to motivate participants to achieve higher levels of
performance and skill.
42
CrossFit was founded by Greg and Lauren Glassman in
1995. Since the opening of the first CrossFit gym in Santa Cruz, CA, the number of affiliated gyms has grown
to over 3,000 worldwide (as of June, 2011). Although
one may join a CrossFit gym or take a training course
on elements of CrossFit, it is essentially a free program.
CrossFit’s main web site, www.crossfit.com, contains almost everything one would need to learn regarding the
basics of the fitness program or to be an active part of
the CrossFit community. In addition, CrossFit workouts
often require minimal (e.g., free weights, pull up bar)
or no equipment (e.g., bodyweight workouts) making
it an attractive option for fire departments with limited
budgets. Each day the CrossFit web site posts a “Workout of the Day” (WOD) and hundreds of people post
their comments and performance on these WODs to the
community blog provided on the site. A large number
of WODs have been designed specifically for firefighters
and these routines can be “scaled” or modified to more
closely match the skill level or physical limitations of
participants.
CrossFit uses three overlapping standards to define
fitness, all of which are designed to emphasize broad
and general fitness rather than specialization. The first
CrossFit fitness standard suggests that a firefighter
would only be adequately fit if they are competent in all
10 of these skills:
1. Cardiovascular/respiratory endurance – The ability of body systems to gather, process, and deliver oxygen.
2. Stamina – The ability of body systems to process, deliver, store, and utilize energy.
3. Strength – The ability of a muscular unit, or combi-
nation of muscular units, to apply force.
4. Flexibility – the ability to maximize the range of mo-
tion at a given joint.
5. Power – The ability of a muscular unit, or combina-
tion of muscular units, to apply maximum force in minimum time.
6. Speed – The ability to minimize the time cycle of a repeated movement.
7. Coordination – The ability to combine several distinct movement patterns into a singular distinct movement.
8. Agility – The ability to minimize transition time from one movement pattern to another.
9. Balance – The ability to control the placement of the body’s center of gravity in relation to its support base.
10. Accuracy – The ability to control movement in a given direction or at a given intensity.
CrossFit workouts are designed to positively impact
all of these skills and to not overemphasize any to the
exclusion of the others.
The second standard of fitness is based on the assumption that highly fit individuals will be able to perform
well at every physical task imaginable. For instance, a
highly fit firefighter may not have the fastest time in a
5 kilometer run or possess a record-setting deadlift, but
they would perform as well or better than anyone other
than a “specialist” (e.g., Olympic runner or champion
power lifter) in both running and weightlifting tasks.
Because of this, CrossFit workouts are highly varied and
encourage training in both familiar and unfamiliar tasks
in varying combinations.
CrossFit’s third standard of fitness is based on the three
metabolic pathways that provide energy for human
activity. These systems provide energy for short, high
intensity activities such as a100-yard dash (phosphagen system), moderate powered activities such as a 400
meter sprint (glycolytic system), or more lengthy, less
intense activities such as a marathon (oxidative system).
Although no energy system provides all of the energy
required to perform an activity, the degree to which
each contributes is primarily determined by the inten-
sity of the exercise followed by its duration.84 Although
CrossFit prescribes workouts that stress all three energy
systems, there is an emphasis on activities which are
primarily powered by the glycolytic system given its
generalizability to a broad range of activities.
CrossFit’s methodology emphasizes performing functional movements at high intensity and to continually vary the specific workouts performed over time.
CrossFit argues that this methodology results in a high
level of general fitness, shorter exercise times and less
boredom, and requires relatively low-cost exercise
equipment. Workout programming can be modified to
accommodate the unique schedules of firefighters.
Given that CrossFit programming is provided without
charge on the CrossFit.com website, requires relatively
low-cost equipment, and reduces the time-commitment
required for exercise compared to typical workout
programs, it is an attractive option for fire departments.
In addition, CrossFit incorporates the health benefits
of HIT and weightlifting while increasing a firefighter’s
ability to perform functional movements commonly
encountered in the field and on the fire ground.
Notes
1. See the guidelines on the ACSM website at:
www.acsm.org/AM/Template.cfm?Section=Home_Page&TEMPLATE=/CM/HTMLDisplay.cfm&CONTENTID=7764`
2. The National Physical Activity Plan can be found at: www.physicalactivityplan.org/theplan.php
3. Information about the IAFF/IAFC Wellness Fitness Initiative can be found at: www.iaff.org/hs/wfiresource/default.html
4. The NFPA Standard on Health-Related Fitness Programs for Fire Department Members:
www.nfpa.org/aboutthecodes/AboutTheCodes.asp?DocNum=1583&cookie_test=1
5. USDA Nutrition Guidelines: www.choosemyplate.gov/
6. AHA Diet and Lifestyle Recommendations:
www.heart.org/HEARTORG/GettingHealthy/Diet-and-Lifestyle-Recommendations_UCM_305855_Article.jsp
7. Pollan, M (2009). Food Rules: An Eater’s Manual. New York: The Penguin Press.
8. List extracted from the Nestle website:
www.nestleprofessional.com/united-states/en/BrandsAndProducts/Brands/HOT_POCKETS/Pages/11007747.aspx
9. Michael Pollan (2008). In Defense of Food: An Eater’s Manifesto. New York: The Penguin Press.
10. Some of these recommendations are adapted from Sisson, M (2009). The Primal Blueprint. Malibu, CA: Primal Nutrition, Inc. Mark writes one of the most popular health blogs on the Internet (www.marksdailyapple.com) and there are firehouses which follow his eating plan. Mark’s book is easy to understand and provides a comprehensive guide to health and fitness which would benefit any firefighter.
11. There are several websites for the Slow Food movement. For example, see: www.slowfood.com and www.slowfoodusa.org.
43
12. Cordain, L., Eaton, S.B., Sebastian, A., Mann, N., Lindeberg, S., Watkins, B.A., O’Keefe, J.H., Brand-Miller-J. (2005). Origins and evolution of the Western diet: health implications for the 21st century. American Journal of Clinical Nutrition, 81,
341-354.
13. For interesting reviews of the lives and health of ancient and current hunter-gatherers with a focus on diet and physical
activity see: Cordain, L., Friel, J. (2005). The Paleo Diet for Atlhetes: A Nutritional Formula for Peak Athletic Performance. Emmaus, PA: Rodale. Wolf, R. (2010). The Paleo Solution: The Original Human Diet. Las Vegas, NV: Victory Belt
Publishing. Also see a recent review on the impact of the modern agricultural on human height: Mummert, A., Esche, E., Robinson, J., Armelagos, G.J. (2011). Stature and robusticity during the agricultural transition: Evidence from the
bioarchaeological record. Economics and Human Biology 9, 284-301.
14. For instance, see http://thepaleodiet.com/store/acne-products-2/
15. Willett, W. (2003). Concepts and Controversies on Diet: Stop Recommending Low-Fat Diets! The Permanente Journal, 7, 24-33.
16. International Association of Fire Fighters. The fire service joint labor management wellness-fitness initiative, 3rd Edition. Washington, DC: IAFF, 2008.
17. Bjerke W. Health and fitness programs for firefighters. Strength and Conditioning Journal, 2011, 33:55-57.
18. Centers for Disease Control and Prevention (CDC). Fatalities among volunteer and career firefighters – United States, 1994-
2004. Morbidity and Mortality Weekly Report, 2006;55:453-455.
19. National Institute of Standards and Technology (NIST). The Economic Consequences of Firefighter Injuries and Their
Prevention. Arlington, VA: TriData Corporation, 2004.
20. Mancuso J. Overweight and obesity on the Omaha Fire Department. Emmitsburg, MD: Executive Fire Officer Program Paper, National Fire Academy, 2003.
21. Donovan R, Nelson T, Peel J, Lipsey T, Voyles W, Israel RG. Cardiorespiratory fitness and the metabolic syndrome in
firefighters. Occupational Medicine, 2009;59:487-492.
22. Tsismenakis AJ, Christophi CA, Burress JW, Kinney AM, Kim M, Kales SN. The obesity epidemic and future emergency responders. Obesity, 2009;17:1648-1649.
23. Poston, W.S.C., Haddock, C.K., Jahnke, S.A., Jitnarin, N., Tuley, B.C., & Kales, S.N. (2011). The prevalence of overweight, obesity, and substandard fitness in a population-based firefighter cohort. Journal of Occupational and Environmental
Medicine, 53, 266-274.
24. Clark S, Rene A, Theurer WM, Marschall M. Association between body mass index and health status in firefighters. Journal of Occupational and Environmental Medicine, 2002;44:940-946.
25. Kales SN, Polyhronopoulos GN, Aldrich JM, Leitao EO, Christiani DC. Correlates of body mass index in hazardous
materials firefighters. Journal of Occupational and Environmental Medicine, 1999;41:589-595.
26. Durand G, Tsismenakis AJ, Jahnke SA, Baur DM, Christophi CA, Kales SA. Firefighters physical activity: Relation to fitness and cardiovascular disease risk. Medicine & Science in Sports & Exercise. In press.
27. Soteriades ES, Hauser R, Kawachi I, Liarokapis D, Christiani DC, Kales SN. Obesity and cardiovascular disease risk factors in firefighters: A prospective cohort study. Obesity Research, 2005;13:1756-1763.
28. Elsner KL, Kolkhorst FW. Metabolic demands of simulated firefighting tasks. Ergonomics, 2008;51:1418-1425.
29. Michaelides MA, Parpa KM, Thompson J, Brown B. Predicting performance on firefighter’s ability test from fitness
parameters. Research Quarterly in Exercise & Sports, 2008;79:468-475.
30. Rhea MR, Alvar BA, Gray R. Physical fitness and job performance of firefighters. Journal of Strength and Conditioning, 2004;18:348-352.
31. Kaufman KR, Brodine S, Shaffer R. Military training-related injuries. Surveillance, research, and prevention. American
Journal of Preventive Medicine, 2000;18:54-63.
32. National Research Council (NRC). Assessing Fitness for Military Enlistment: Physical, Medical, and Mental Health
Standards. Committee on the Youth Population and Military Recruitment: Physical, Medical, and Mental Health Standards. In Paul R. Sackett and Anne S. Mavor (Eds.), Board on Behavioral, Cognitive, and Sensory Sciences, Division of Behavioral and Social Sciences and Education. Washington, DC: The National Academies Press, 2006.
33. Taylor MK, Markham AE, Reis JP, Padilla GA, Potterat EG, Drummond SPA, Mujica-Parodi LR. Physical fitness influences stress reactions to extreme military training. Military Medicine 2008;173:738-742.
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34. United States Department of Health and Human Services (USDHHS). Physical activity and health. A report of the Surgeon General. Alanta, GA: Centers for Disease Control and Prevention, 1996.
35. Lollgen H, Bockenhoff A, Knapp G. Physical activity and all-cause mortality: An updated meta-analysis with different
intensity categories. International Journal of Sports Medicine, 2009;30:213-224.
36. Wei M, Kampert JB, Barlow CE, Nichaman MZ, Gibbons LW, Paffenbarger RS, Blair SN. Relationship between low cardio
respiratory fitness and mortality in normal-weight, overweight, and obese men. JAMA, 1999;282:1547-1553.
37. Farrell SW, Braun L, Barlow CE, Cheng YJ, Blair SN. The relation of body mass index, cardiorespiratory fitness, and all-cause
mortality in women. Obesity Research, 2002;10:417-423.
38. Farrell SW, Fitzgerald SJ, McAuley PA, Barlow CE. Cardiorespiratory fitness, adiposity, and all-cause mortality in women. Medicine & Science in Sports & Exercise, 2010;42:2006-2012.
39. Fogelholm M. Physical activity, fitness and fatness: Relations to mortality, morbidity, and disease risk factors. A systematic review. Obesity Reviews, 2010;11:202-221.
40. Blair SN, Kampert JB, Kohl WH, Barlow CE, Macera CA, Paffenbarger RS, Gibbons LW. Influences of cardiorespiratory
fitness and other precursors on cardiovascular disease and all-cause mortality in men and women. JAMA, 1996;276:205-210.
41. Church TS, Kampert JB, Gibbons LW, Barlow CE, Blair SN. Usefulness of cardiorespiratory fitness as a predictor of all-cause and cardiovascular disease mortality in men with systemic hypertension. American Journal of Cardiology, 2001;88:651-656.
42. Blair SN, Cheng Y, Holder JS. Is physical activity or physical fitness more important in defining health benefits? Medicine & Science in Sports & Exercise, 2001;33 (6 Suppl):S379-S399.
43. Haskell WL, Lee IM, Pate RR, Powell KE, Blair SN, Franklin BA, Macera CA Health GW, Thompson PD, Bauman A.
Physical activity and public health: Updated recommendation for adults form the American College of Sports Medicine and the American Heart Association. Medicine & Science in Sports & Exercise, 2007;116:1081-1093.
44. O’Brien K. Wellness and fitness in the fire service. Exercise for Men Only, 2009;25:114-115.
45. Dolan M. Injury/illness reduction plan through a joint program conceived between local health care provider and the fire department. Emmitsburg, MD: Executive Fire Officer Program Paper, National Fire Academy, 2003.
46. Sevier TL. The industrial athlete? Occupational and Environmental Medicine, 2000;57:285.
47. Roberts MA, O’Dea J, Boyce A, Mannix ET. Fitness levels of firefighter recruits before and after a supervised exercise
training program. Journal of Strength and Conditioning Research, 2002;16:271-277.
48. Reid EL, Morgan RW. Exercise prescription. A clinical trial. American Journal of Public Health, 1979;69:591-595.
49. Elliot DL, Goldberg L, Kuehl KS, Moe EL, Breger RKR, Pickering MA. The PHLAME (Promoting Healthy Lifestyles:
Alternative Models’ Effects) firefighter study: Outcomes of two models of behavior change. Journal of Occupational and Environmental Medicine, 2007;49:204-213.
50. Paton CD, Hopkins WG. Effects of high-intensity training on performance and physiology of endurance athletes.
Sportscience, 2004;8:25-40.
51. Kemi OJ, Wisloff U. High-intensity aerobic exercise training improves the heart in health and disease. Journal of
Cardiopulmonary Rehabilitation and Prevention, 2010;30:2-11.
52. Nilsson BB, Westheim A, Risberg MA. Long-term effects of a group-based high-intensity aerobic interval-training program in patients with chronic heart failure. American Journal of Cardiology, 2008;102:1220-1224.
53. Westcott WL, Annesi J, D’Arpino T. Battle-ready strength training. Fitness Management, 2004;20:32-36.
54. Gibala MJ, McGee SL. Metabolic adaptations to short-term high-intensity interval training: A little pain for a lot of gain? Exercise and Sport Science Reviews, 2008;36:58-63.
55. Schoenfeld B, Dawes J. High intensity interval training: Applications for general fitness training. Strength & Conditioning Journal, 2009;31:44-46.
56. Tabata I, Nishimura K, Kouzaki M, Hirai Y, Ogita F, Mivachi M, et al. Effects of moderate-intensity endurance and high-i
ntensity intermittent training on anaerobic capacity and VO2 max. Medicine & Science in Sports & Exercise, 1996;28:
1327-1330.
45
57. Yoshioka M, Doucet E, St-Pierre S, Almeras N, Richard D, Labrie A, et al. Impact of high-intensity exercise on energy
expenditure, lipid oxidation, and body fatness. International Journal of Obesity and Related Metabolic Disorders, 2001;25:332-339.
58. Lekhi C, Gupta PH, Singh B. Influence of exercise on oxidant stress products in elite Indian cyclists. British Journal of Sports Medicine, 2007;41:691-693.
59. Gibala MJ, Little JP, van Essen M, Wilkin GP, Burgomaster KA, Safdar A, et al. Short-term sprint interval versus
traditional endurance training: Similar initial adaptations in human skeletal muscle and exercise performance. Journal of Physiology, 2006;575:901-911.
60. Berger NJ, Tolfrey K, Williams AG, Jones AM. Influence of continuous and interval training on oxygen uptake on kinetics. Medicine & Science in Sports & Exercise, 2006;38:504-512.
61. Burgomaster KA, Howarth KR, Phillips SM, Rakobowchuk M, MacDonald MJ, McGee SL, et al. Similar metabolic
adaptations during exercise after low volume sprint interval and traditional endurance training in humans. Journal of
Physiology, 2008;586:151-160.
62. Tremblay A, Simoneau JA, Bouchard C. Impact of exercise intensity on body fatness and skeletal muscle metabolism.
Metabolism, 1994;43:814-818.
63. Tsekouras YE, Magkos F, Kellas Y, Basisoukas KN, Kavouras SA, Sidossis LS. High-intensity interval aerobic training reduces hepatic very low-density lipoprotein-triglyceride secretion rate in men. American Journal of Physiology – Endocrinology & Metabolism, 2008;295:E851-E858.
64. Talanian JL, Galloway SD, Heigenhauser GJ, Bonen A, Spriet LL. Two weeks of high-intensity aerobic interval training in
creases the capacity for fat oxidation during exercise in women. Journal of Applied Physiology, 2007;102:1439-1447.
65. Burgomaster KA, Hughes SC, Heignenhauser GJF, Bradwell SN, Gibala MJ. Six sessions of sprint interval training increases muscle oxidative potential and cycle endurance capacity in humans. Journal of Applied Physiology, 2005;98:1985-1990.
66. Dalleck L, Bushman TT, Crain RD, Gajda MM, Koger EM, Dersksen LA. Dose-response relationship between interval
training frequency and magnitude of improvement in lactate threshold. International Journal of Sports Medicine 2010;31:567-571.
67. Kotzamanidis C, Chatzopoulos D, Michailidis C, Papaiakovou G, Patikas D. The effect of a combined high-intensity strength and speed training program on the running and jumping ability of soccer players. Journal of Strength and Conditioning Research, 2005;19:369-375.
68. Paton CD, Hopkins WG. Combining explosive and high-resistance training improves performance in competitive cyclists. Journal of Strength & Conditioning Research, 2005;19:826-830.
69. Turner AN. Training the aerobic capacity of distance runners: A break from tradition. Strength and Conditioning Journal, 2001;33:39-42.
70. Butcher SJ, Jones RL. The impact of exercise training intensity on change in physiological function in patients with chronic obstructive pulmonary disease. Sports Medicine, 2006;36:307-325.
71. Kraemer WJ, Ratamess NA. Hormonal responses and adaptations to resistance exercise and training. Sports Medicine, 2005;35:39-361.
72. Hoffman JR, Cooper J, Wendell M, Kang J. Comparison of Olympic vs. traditional power lifting training programs in
football players. Journal of Strength & Conditioning Research, 2004;18:129-135.
73. Sentija, D, Marsic T, Dizdar D. The effects of strength training on some parameters of aerobic and anaerobic endurance.
Collegium Antropologicum, 2009;33:111-116.
74. Nakao M, Inoue Y, Murakami H. Longitudinal study of the effect of high intensity weight training on aerobic capacity.
European Journal of Applied Physiology and Occupational Physiology, 1995;70:50-25.
75. Conroy BP, Kraemer WJ, Maresh CM, Fleck SJ, Stone, M. H., Fry, A. C., et al. Bone mineral density in elite junior Olympic weightlifters. Medicine & Science in Sports & Exercise, 1993;25:1103-1109.
76. Jones CS, Christensen C, Young M. Weight training injury trends: A 20-year survey. Physician and Sportsmedicine, 2000;28:61-72.
77. For examples, see: www.crossfitfirefighters.com/; www.highlandsfirecrossfit.com/; http://crossfitbrightonfire.typepad.com/; http://firegroundfitness.blogspot.com/; www.hitechgym.com/CrossfitSMAC/).
78. Contreras M. The fire service and CrossFit. CrossFit Journal, 2006;51:1-3.
79. Kilgore, L. (2007, March). Putting out fires. CrossFit Journal, 2007;55:1-3. Retrieved June 8, 2011, from
http://library.crossfit.com/premium/pdf/55_07_putting_out_fires.pdf?e=1307549227&h=4c5dfcd38f6972d6bf315d12ea05ce4c.
46
80. Morris M, Burrow J. To serve, protect—and sweat. CrossFit Journal, 2009 (May). Retrieved June 8, 2011, from
http://library.crossfit.com/premium/pdf/CFJ_NorthshoreFire.pdf?e=1307549540&h=3fe35284a1118656e4259724f8c415a4.
81. CrossFit, Inc. The Crossfit Level 1 Training Guide, obtained from CrossFit, Inc., 1250 Connecticut Avenue, N.W., Suite 200, Washington, DC 20036, 2009. (Note: Unless otherwise indicated, basic information presented in this chapter on the CrossFit program is taken from this manual).
82. Sears B, Lawren W. The Zone: A dietary road map to lose weight permanently. New York, NY: HarperColline Publishers, Inc., 1995.
83. Cordain L, Friel J. The Paleo diet for athletes. Emmaus, PA: Rodale Press, 2005.
84. Cramer JT. Bioenergetics of exercise and training. In T.R. Baechle & R.W. Earle (Eds.), Essentials of strength training and conditioning (3rd ed.) (pp. 21-39). Champaign, IL: Human Kinetics, 2008.
85. Glassman G. Police training. CrossFit Journal, 2003 (March); Retrieved June 8, 2011, from
http://library.crossfit.com/free/pdf/policetng_Mar03.pdf.
86. Sam, D. (2005, April). A soldier’s perspective on functional fitness. CrossFit Journal 2005 (April);32:1-3. Retrieved June 8, 2011, from http://library.crossfit.com/free/pdf/32_05_Functional_Fitness.pdf.
47
Chapter 5
Recommendations for the
Fire Service for Combating
Obesity and Increasing Fitness
Nutrition I Fitness I Water I Meats I Eggs I Fish
Chapter 5 Recommendations for the Fire Service for Combating Obesity and Increasing Fitness
There are a number of initiatives that could dramatically improve the health and fitness of firefighters and
significantly reduce the rate of overweight and obesity
in the fire service. The recommendations in this chapter
will focus on two issues that can propel the fire service
into a more positive future in terms of health and fitness: 1) nutrition in the firehouse, and 2) fitness assessments and guidelines.
These recommendations will require firefighter buy-in,
in addition to leadership endorsement. Fortunately, the
culture in the fire service is ready for a paradigm shift
when it comes to fitness and nutrition. This can be seen
in changes already being made. For instance, there was
a time when many, if not most, firefighters smoked
cigarettes, but today the culture in many areas of the
country has shifted radically. If this trend continues, it
won’t be long before it will be rare to find a firefighter
who smokes, and tobacco use will be considered incompatible with the job duties. Similar paradigm shifts
have happened in matters of firefighter safety, including
wearing seatbelts and the use of SCBAs, in a number
of regions. It is time for this same paradigm shift to occur regarding the diets and fitness of firefighters – who
should see themselves as industrial athletes that must be
ready for any contingency.
Nutrition Recommendations
Healthy nutrition is one of the most important components of health and fitness. It is difficult, if not impossible, to overcome the negative impact of an unhealthy
diet with physical activity. A change in eating habits is
critical to reversing the obesity epidemic facing our nation’s fire service.
Eating has become a cultural phenomenon which has
meaning well beyond how food nourishes the body or
protects against disease. To complicate things further,
many firehouses are in areas of the country where it is
difficult to access healthy foods, and some firefighters
face financial hardships that make it harder to afford
healthier food options. Healthy eating can be even more
challenging without the support of friends and family.
As a result, eating an “ideal” diet may seem out of reach
for some.
Despite the challenges, it is important to remember that
nutrition will either enhance or inhibit a firefighter’s
readiness. Many individuals in the fire service, even
those in very challenging circumstances, have transformed their eating habits and are now reaping the
49
rewards of improved health. Learning about nutrition
and developing healthy eating habits is an important
investment for your health, family, and crew.
Firefighters need to shift their nutrition, as much as possible, toward natural, whole foods and away from processed carbohydrates and sugar. Although an occasional
celebration can be harmless, regularly eating foods that
are toxic to your body will only worsen the epidemic of
obesity and low fitness that plagues the fire service.
Here are 10 steps to take control of your nutrition:
1. Decide to get serious about nutrition. Think carefully about what you eat, plan ahead, and stock the
kitchen at the firehouse with healthy foods and snacks.
It is difficult to maintain a healthy diet when “what’s
for dinner” is determined at the last moment by what
is on sale at the local market. We have been misled to
believe that food should be fast, cheap, and require little
thought – a belief that is wreaking havoc on our health.
The community is counting on firefighters to be ready
to respond, and having a proper diet plays a large role
in physical readiness.
2. Get informed. Regularly visit reputable nutrition web
sites by individuals who have worked and/or are popular with firefighters and other industrial athletes. Some
of these include:
>Mark’s Daily Apple (www.marksdailyapple.com). Mark Sisson is a former high-level endurance athlete and the author of one of the most popular nutrition sites on the Internet. There are firehouses that follow his dietary advice.
>Robb Wolf: Revolutionary Solutions to Modern Life (www.robbwolf.com). Robb Wolf, the co-owner of
NorCal Strength and Conditioning, is one of the lead-
ing experts on performance nutrition and has worked with many firefighters on their diet and fitness.
>The Paleo Diet (http://thepaleodiet.com/). This is the
web site of Dr. Loren Cordain, Professor in the Department of Health and Exercise Science at Colo-
rado State University and author of The Paleo Diet for Athletes.
>Gary Taubes (www.garytaubes.com/). Guy Taubes is the author of Good Calories Bad Calories and Why We Get Fat. He regularly blogs on nutritional issues.
>Food Inc. (www.foodincmovie.com/). This is the
official web site of the identically-named documentary and contains nutritional advice.
There are many other quality nutrition sites on the Internet. Be sure to conduct thorough searches and weigh
the pros and cons of each site and its recommendations.
Take the initiative to expand your nutrition education.
3. Encourage a culture of healthy eating in the department. It is difficult to maintain good nutrition when
efforts are met with negativity from others. Publically
support a firefighter who suggests having healthier
snacks at the firehouse. Ask local dietitians or fitness
professionals to come speak about healthy eating at
department meetings to discuss ways to overcome barriers to healthy eating such as cost and access. Plan a
series of discussions about nutrition and the fire service
during department training. Start a movement to limit
junk food in the firehouse to reduce temptation, and
share ideas about how to eat healthy with your fellow
firefighters.
4. Reduce the amount of processed foods (e.g., foods
that come in a wrapper or box) and refined sugars in
the home and the firehouse. In particular, avoid white
flour, white flour products, and white rice. Most people
report that after about two to four weeks of restricting
these unhealthy, processed carbohydrates, their cravings for them substantially lessen. Stop drinking sodas
and other sweetened beverages, including sports and
energy drinks. These products are often expensive and
detract from overall health and fitness. For example,
if you drink two 20-oz Cokes and two 8-oz cans of
Monster Energy Drink per day, you are consuming over
180 grams of sugar in drinks alone! Drinks filled with
mystery ingredients are not necessary to feel energetic
once an improved diet is adopted.
5. Eat high-quality vegetables and fruits. Focus on eating
the highest-quality food that you can find. Food is one
area where cheap is not a bargain; you will pay dearly
in how you feel, your health, and your quality of life if
cost is the only consideration for what you eat. Many
people will not hesitate to spend money on alcohol,
cigarettes, entertainment, etc., but will insist that their
food be inexpensive. Some departments may lack access
to, or the resources for, quality produce. Keep the following suggestions in mind to make the best decisions
for you and your department:
50
First Choice: Home-grown fruits and vegetables. There are many benefits to growing at least a portion of your food. Start a garden either at your home or the firehouse and learn to freeze and preserve food for off-season use. Growing food brings families and fire crews together around an activity that will inevitably lead to a higher quality of life.
Second Choice: Locally-grown fruits and vegetables. Although eating organic products has many benefits, some local farms do not have the resources to be
certified organic even though they use progressive farming practices. Go to a local farmers’ market, get to know a farmer, and ask the community to donate food they grow to the firehouse. Eat local, organicallygrown food whenever possible. Plug your zip code into the Eat Well Guide’s search engine at
www.eatwellguide.org and visit the farmer’s markets and purchase a share in Community Supported
Agriculture.
Third Choice: Fresh frozen fruits and vegetables. Most often fruits and vegetables are frozen at their peak of
freshness. Do not let the lack of access to fresh pro-
duce deter you from eating plenty of fruits and veg-
etables. Focus on variety, particularly greens and berries, but limit high-glycemic index starches such as white potatoes.
Fourth Choice: Fruits and vegetables shipped over long distances to your community. The bottom line is that it is better to fill your diet with fruits and veg-
etables than to avoid them because your community has limited access to higher-quality produce. Just be sure to wash all vegetables and fruits thoroughly before eating them.
5. Focus on high-quality meats and eggs and limit processed meats. Select meats and eggs that are naturally
(e.g., grass-fed beef, wild caught fish, hormone free) and
locally produced when possible. Try to avoid highlyprocessed meats such as cold cuts.
6. Round off your diet with nuts and seeds. Great options include almonds, macadamia nuts, and walnuts.
Nuts and seeds are packed with healthy nutrients and
help to keep you feeling full and energetic. Try to avoid
eating peanuts – which are not technically nuts – since
they lack the same nutritional value and are associated
with peanut allergies.
7. Eliminate trans-fats and high-fructose corn syrup from
your diet. This is getting easier to do as more and more
food manufacturers eliminate both of these problematic
ingredients in their products. However, they are still out
there so read the food labels.
8. Be sure to drink plenty of water and unsweetened tea.
Come to work hydrated and stay that way throughout
the day.
9. Take a multivitamin/antioxidant supplement and
omega-3 fish oil capsules. Choose high-quality products, including mercury-free fish oil. Many discount
stores now carry high-quality supplements at affordable
prices.
10. Rethink treats and snacks. Michael Pollan wrote
in his book Food Rules that we should “treat treats as
treats.”1 Behavioral scientists talk about using “stimulus
control” to help change a habit. For example, if you
are trying to change a habit like eating candy, then do
not keep candy around. It is much more difficult to stay
healthy in a firehouse filled with unhealthy food. Talk to
your crew about filling your environment with healthy
foods and getting rid of those that will ultimately make
you sick. Saving treats for truly special occasions will allow them to be appreciated and savored.
Fitness Assessments and Guidelines
Currently, there are no mandatory national standards
for fitness that set specific requirements for firefighters. Carefully developed guidelines would serve to
educate fire service personnel on what fitness domains
are important to their work, how to achieve sufficient
performance in those domains, and provide motivation to maintain the desired level of fitness. Departments should consider adopting fitness guidelines and
conducting fitness assessments for personnel. The fire
department should work to create and sustain a culture of health and wellness and support personnel as
they pursue their fitness goals. Fitness assessments and
guidelines can be designed to reflect the capabilities and
needs of the department and do not need to be costly or
require expensive equipment.
While some firefighters have expressed concerns about
the adoption of fitness standards, many fire service
leaders and occupational health experts have noted
the growing negative impact of an absence of a consistent and comprehensive approach to fitness in the fire
service.2-3 In addition to contributing to the epidemic of
obesity and low fitness among firefighters, having an inadequate focus on fitness is a safety risk. Even a simple
fitness assessment program would provide valuable
information on fitness domains where a firefighter may
need remediation, which would result in lower rates of
injury and increased occupational effectiveness.4
51
It is clear that many firefighters are ambivalent regarding mandatory fitness standards. For example, the
National Development and Research Institutes’ research
team recently completed a national qualitative study of
firefighter and fire service leadership perception about
general health, wellness, and safety with 332 career and
95 volunteer firefighters from 34 different departments
across the US.5 When asked about their feelings regarding fitness testing, many responded with concerns about
how test results would be used, the repercussions of not
passing, and the validity or applicability of different
fitness tests to actual firefighting tasks. It also should
be noted, however, that many firefighters felt that low
fitness was a definite problem in the fire service and that
something needed to be done to address it. There is a
palpable tension between the widely acknowledged fact
that effective firefighting requires high levels of fitness
and the epidemic of low fitness and obesity in the fire
service.
Adopting fitness guidelines may be difficult for some
volunteer and career fire departments to implement due
to lack of funding or support, particularly with regard
to providing fitness training facilities and equipment.
For example, outfitting a traditional gym that includes
a treadmill, elliptical trainer, and a universal weight
machine or similar multitasking resistance equipment
could cost thousands of dollars, making it completely
out of reach for many fire departments. Luckily, expensive equipment is unnecessary for a quality workout.
Many exercises that can improve firefighter fitness and
job performance can be conducted using equipment
already found at the firehouse or nearby free resources.
These may include old hoses, empty oxygen tanks,
sandbags, old tires, ladders, sledgehammers, training
towers, stairwells, local high school tracks, and stadium
stairways.
Minimal equipment can be used to significantly improve
fitness and meet the rigorous demands of the fire and
emergency services. Underfunded fire departments can
develop fitness programming by emphasizing functional
movements performed at high intensity and utilizing
bodyweight movements. Cost should not be a barrier
to implementing a fitness program for your department.
An excellent fitness program can be developed with
virtually no additional cost or space while engaging in
many of the challenging activities for which firefighters must be prepared, such as breaching doors, tearing
down walls and ceilings, rescuing and carrying victims,
running up and down multiple flights of stairs, etc.
Unlike traditional approaches, this type of fitness program does not require a substantial financial investment
or space. For example, a typical workout could include
stair climbing, sprint intervals while carrying hoses,
pull-ups on a door jamb, flipping a tractor tire, pulling
bundled hoses up several stories with ropes, pushups,
and sit-ups. None of the equipment used in this workout needs to be purchased. This sample workout is
challenging, mimics actual firefighting activities, and
could be completed by several firefighters simultaneously, allowing a crew to be able to benefit from camaraderie and competition. The difficulty and intensity level
could be easily increased by having firefighters wear
their turnout gear. In addition, a functional workout
such as this is time-efficient because of the emphasis
on performing at high intensity while hitting multiple
important fitness domains (e.g., aerobic and anaerobic endurance, muscle strength and endurance, etc.).
Examples of different workouts can be found for free at
Crossfit.com.
To adopt fitness guidelines or standards, departments
can find guidance from the Fire Service Joint Labor
Management Wellness/Fitness Initiative (WFI), the
National Volunteer Fire Council’s Health and Wellness Advocate Program, and NFPA 1583: Standard on
Health-Related Fitness Programs for Fire Department
Members.6-8 These resources suggest that, at a minimum, the following fitness domains should be assessed
annually: 1) aerobic capacity, 2) body composition, 3)
muscular strength, 4) muscular endurance, and 5) flexibility. They also provide guidance to fire departments
and firefighters on how to structure comprehensive
fitness programs, develop and utilize peer fitness trainers
or advocates, and how to conduct fitness assessments
of each of the five fitness domains. Departments should
look to these resources for guidance when developing
and adopting fitness guidelines that fit their needs and
capabilities.
In addition, anaerobic endurance, a domain that is not
discussed in the WFI, should also be included. Anaerobic endurance involves engaging in maximum work
efforts without oxygen for short periods of time so the
that the body is working hard enough that the demands
for oxygen and fuel exceed the rate of supply and the
muscles have to rely on the stored reserves of fuel. Rhea
and associates identified anaerobic endurance as being
strongly associated with all tested job performance measures for firefighters (e.g., performance total, hose pull,
victim drag, stair climb, and equipment hoist). This domain can be tested with a short distance sprint (400m)
and can be trained for by including sprint intervals,
plyometric drills, etc., into a firefighter’s fitness program.
Anaerobic endurance was found to be a more powerful
predictor of firefighter job task completion than aerobic
capacity and most muscular endurance tests.4
Any fire service fitness assessment program should
be composed of tasks that are functional and mimic
actual firefighting activities. Test domains should follow
firefighting, rescue, and emergency medical functions
so that all firefighters develop a level of fitness that
prepares them for a variety of relevant tasks, situations,
and environments. This is consistent with previous
recommendations for firefighter fitness in that multiple
fitness domains will be assessed, but evaluating domains
using more ecologically valid and job-relevant tasks
would be more compelling to firefighters without necessarily sacrificing quality.
References
1. Pollan, M. (2009). Food Rules: An Eater’s Manual. New York, NY: Penguin Group.
2. Smith D, Horn G, Goldstein E, Petruzzello SJ for the Firefighter Life Safety Research Center. Firefighter fatalities and injuries: The role of heat stress and PPE. Urbana-Champaign, IL: University of Illinois Fire Service Institute, 2008.
3. Garver JN, Jankovitz KZ, Danks JM, Fittz AA, Smith HS, Davis SC. Physical fitness of an industrial fire department vs. a municipal fire department. Journal of Strength and Conditioning Research 2005;19:310-317.
4. Rhea MR, Alvar BA, Gray R. Physical fitness and job performance of firefighters. Journal of Strength and Conditioning 2004;18:348-352.
5. Jahnke SA, Poston WSC, Jitnarin N, Haddock CK. Health Concerns of the U.S. Fire Service: Perspectives from the Firehouse. American Journal of Health Promotion. In press.
6. International Association of Firefighters (IAFF) (2008). The Fire Service Joint Labor Management Wellness-Fitness Initiative. 3rd ed. Washington, DC.
52
7. National Fire Protection Association. NFPA 1582, Standards on Comprehensive Occupational Medicine Programs for Fire Departments. Quincy, MA: National Fire Protection Association; 2006.
8. National Volunteer Fire Council (NVFC) (2003). Heart Healthy Firefighter Program Health and Wellness Advocate.
Retrieved from http://healthy-firefighter.org/workshops.
Notes
1. Donovan R, Nelson T, Peel J, Lipsey T, Voyles W, Israel RG. Cardiorespiratory fitness and the metabolic syndrome in
firefighters. Occup Med (Lond). 2009;59:487-492.
2. Mancuso J. Overweight and obesity on the Omaha Fire Department. Emmitsburg, MD: National Fire Academy; 2003.
3. Tsismenakis AJ, Christophi, CA, Burress JW, Kinney AM, Kim M, Kales SN. The obesity epidemic and future emergency responders. Obesity 2009;17:1648-1649.
4. Poston, W.S.C., Haddock, C.K., Jahnke, S.A., Jitnarin, N., Tuley, B.C., & Kales, S.N. (2011). The prevalence of overweight, obesity, and substandard fitness in a population-based firefighter cohort. Journal of Occupational and Environmental Medicine, 53, 266-274.
5. Clark S, Rene A, Theurer WM, Marschall M. Association between body mass index and health status in firefighters. J Occup Environ Med, 2002;44:940-946.
6. Kales SN, Polyhronopoulos GN, Aldrich JM, Leitao EO, Christiani DC. Correlates of body mass index in hazardous
materials firefighters. J Occup Environ Med, 1999;41:589-595.
7. Durand G, Tsismenakis AJ, Jahnke SA, Baur DM, Christophi CA, Kales SA. Firefighters physical activity: Relation to fitness and cardiovascular disease risk. Medicine & Science in Sports & Exercise, In press.
8. Soteriades ES, Hauser R, Kawachi I, Christiani DC, Kales SN. Obesity and risk of job disability in male firefighters. Occup Med (Lond), 2008;58:245-250.
9. Yoo HL, Franke WD. Prevalence of cardiovascular disease risk factors in volunteer firefighters. Journal of Occupational and Environmental Medicine, 2009;51:958-962.
10. Centers for Disease Control and Prevention (CDC). Fatalities among volunteer and career firefighters – United States, 1994-
2004. Morbidity and Mortality Weekly Report, 2006;55:453-455.
11. National Institute of Standards and Technology (NIST). The Economic Consequences of Firefighter Injuries and Their
Prevention. Arlington, VA: TriData Corporation, 2004.
12. Elsner KL, Kolkhorst FW. Metabolic demands of simulated firefighting tasks. Ergonomics, 2008;51:1418-1425.
13. Michaelides MA, Parpa KM, Thompson J, Brown B. Predicting performance on firefighter’s ability test from fitness
parameters. Research Quarterly in Exercise & Sports, 2008;79:468-475.
14. Kaufman KR, Brodine S, Shaffer R. Military training-related injuries. Surveillance, research, and prevention. American
Journal of Preventive Medicine, 2000;18:54-63.
15. National Research Council (NRC). Assessing Fitness for Military Enlistment: Physical, Medical, and Mental Health
Standards. Committee on the Youth Population and Military Recruitment: Physical, Medical, and Mental Health Standards. In Paul R. Sackett and Anne S. Mavor (Eds.), Board on Behavioral, Cognitive, and Sensory Sciences, Division of Behavioral and Social Sciences and Education. Washington, DC: The National Academies Press, 2006.
16. US Fire Administration (USFA). Women’s History Month: Women in USFA. 2010. Retrieved February 14, 2011 from
www.usfa.dhs.gov/media/press/2010releases/030510_mc.shtm.
17. Kales SN, Soteriades ES, Christophi CA, Christiani DC. Emergency duties and deaths from heart disease among firefighters in the United States. New England Journal of Medicine, 2007;356:1207-1215. doi/full/10.1056/NEJMoa060357.
18. Roy TC, Springer BA, McNulty V, Butler NL. Physical fitness. Military Medicine, 2010;175:1419. Air Force Instruction (AFI) 36-2905. Fitness Program. 1 July 2010.
20. Olsen EM. The Marine Corps Physical Fitness Test: The Need to Replace it with a Combat Fitness Test. Marine Corps
University, VA: United States Marine Corps, Command and Staff College, Marine Corps Combat Development Command, 2008.
53
21. Amos JF. A concept for functional fitness. United States Marine Corps, Deputy Commander for Combat Development and Integration, 9 Nov 2006.
22. Smith DL, Liebig JP, Steward NM, Fehling PC. Sudden cardiac event in the fire service: Understanding the causes and
mitigating the risks. Saratoga Springs, NY: First Responder Health and Safety Laboratory, health and Exercise Sciences, Skidmore College, 2010.
23. Muegge CM, Zollinger TW, Saywell RM, Moffatt SM Hanify T, Dezelan LA. CPAT: Putting the test to the test. Fire
Engineering August 1, 2002. Retrieved on June 10, 2011 from www.fireengineering.com/index/articles/display.articles.
fire-engineering.volume-155.issue-8.features.cpat-putting-the-test-to-the-test.html.
24. Williams-Bell FM, Villar R, Sharratt MT, Hughson RL. Physiological demands of the firefighter Candidate Physical Ability Test. Medicine & Science in Sports & Exercise, 2009;41:653-662
25. Sheaff AK, Bennett A, Hanson ED, Kim YS, Hsu J, Shim JK, Edwards ST, Hurley BF. Physiological determinants of the
Candidate Physical Ability Test in firefighters. Journal of Strength and Conditioning Research, 2010;24:3112-3122.
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Addressing the Epidemic of Obesity in the United States Fire Service

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